Mega-events such as the Olympic Games, World Cup, and World Expo aim to leave sustainability legacies (94, 95), yet the mechanisms through which these goals are realized in hotel operations remain underexplored. This study adopts a multiple case study design, analyzing secondary data including sustainability reports, certification documents, and post-event assessments from five host cities—London, Tokyo, Dubai, Rio de Janeiro, and Doha. The findings reveal that mega-events can serve as catalysts for sustainability upgrades in hotels, including energy-efficient technologies, employee training, and guest-oriented green initiatives. However, not all legacies are uniformly positive: issues such as short-lived initiatives, cost burdens, and limited accountability mechanisms persist. This study contributes to tourism and event management literature by demonstrating how hotels, as essential components of tourism infrastructure, operationalize event-time sustainability commitments into longer-term environmental and social value. It also highlights the interplay of motivations (branding, regulation, guest expectations), constraints (financial and operational), and outcomes (emissions reduction, organizational resilience). While many upgrades offer both financial and reputational benefits, others require trade-offs, confirming that sustainability legacies are complex, context-dependent, and not universally “win-win”.

Central to all these attempts at sustainability are hotels, which are the major venues for accommodating the sheer volume of visitors flooding in during mega-events. Hotels are not only among the largest components of a mega-event's environmental footprint through energy, water use, and waste generation (1, 2), but they can also perform pretty well in providing green practices to a global audience and demonstrating the viability of sustainable hospitality operations on a mass scale. The hospitality sector's contribution to mega-event sustainability goes beyond operational efficiency to encompass workforce development, community engagement, and building long-term resilience in destinations.

A driving force behind the push for sustainability is the increasing public expectation for environmental responsibility. Global travelers are more eco-conscious than ever: the World Tourism Organization (UNWTO) reported in 2023 that approximately 73% of tourists prefer to stay in hotels that implement sustainable practices (3). This consumer pattern positions hospitality providers at the leading edge of event sustainability efforts. Hotels accommodate the influx of visitors for mega-events and thus are a major contributor to the event's environmental footprint in energy use, water consumption, and waste generation (1, 2). Hotels additionally have the unique potential to showcase green practices to an international audience and capture the gains of the growing niche of environmentally concerned tourists. The majority of hotel companies have responded by adopting sustainability certifications (e.g., Green Key, EarthCheck, or LEED) and green practices to meet both governmental requirements and traveler expectations (4, 5). For instance, Marriott International has pledged that 100% of its hotels will be certified to an internationally recognized sustainability standard by 2025 (6)—an ambitious goal reflective of industry-wide momentum.

However, it is crucial to acknowledge that not all sustainability efforts provide direct financial returns. While eco-efficiency measures such as energy and water conservation often yield measurable cost savings through reduced utility bills, other important sustainability initiatives may offer primarily indirect or long-term value (7, 8). For example, investments in workforce well-being, community engagement programs, biodiversity conservation, or renewable energy infrastructure may not show immediate return on investment (ROI) but contribute to social sustainability, brand reputation, and long-term resilience (9, 10). This complexity is particularly relevant in the context of mega-events, where hotels may be required to implement comprehensive sustainability measures that go beyond those with clear financial benefits. Understanding this nuanced relationship between sustainability initiatives and their varied outcomes—financial, environmental, and social—is essential for both practitioners and researchers examining the legacy of mega-events on hotel operations.

The concept of legacy in mega-events has evolved significantly over the past two decades. Early conceptualizations focused primarily on economic and infrastructural outcomes (11, 12), but contemporary understanding encompasses environmental, social, and cultural dimensions (13, 14). Preuss (15) refined his earlier definition to emphasize that legacies can be both tangible (infrastructure, venues) and intangible (knowledge transfer, social capital), and that they may manifest differently across stakeholder groups.

For hotels, mega-event legacies are felt in terms of shifts in operations, infrastructure upgrading, and capacity building that lasts beyond the event horizon. These legacies may be comprised of physical capital (energy systems, waste management plants), human capital (skilled staff, sustainability experience), and organizational capabilities (environmental management systems, stakeholder engagement processes). However, theoretical concepts of how these legacies for hotels are built, maintained, and measured are still lacking. This study contributes to legacy theory by investigating the specific processes through which hotels translate event-time sustainability pressures into sustainable operational changes.

Environmental sustainability in mega-events gained prominence following criticism of the ecological impacts of earlier events (16, 17). The Sydney 2000 Olympics marked a turning point with its “Green Games” agenda, though scholars have debated the extent to which these aspirations were realized (18, 19). Subsequent events have increasingly incorporated sustainability into bid documents and operational planning, driven by both regulatory requirements and reputational concerns (20).

The hospitality industry's engagement with sustainability has been extensively documented in academic literature. Early work by Kirk (21) and Bohdanowicz (22) established the business case for environmental management in hotels, focusing primarily on eco-efficiency measures. More recent scholarship has expanded to examine social sustainability dimensions, including workforce development, community engagement, and cultural preservation (23, 24).

Institutional theory provides an effective framework for analyzing how mega-events influence hotel sustainability adoption. DiMaggio and Powell (25) identified three sources of institutional pressures for organizational change: coercive (regulations, mandates), normative (professional standards, certifications), and mimetic (imitation of successful practices). Mega-events create all three sources of pressure simultaneously because hotels are exposed to regulatory demands, industry norms, and competitive pressure to implement sustainable practices. However, the between-event and between-setting heterogeneity of results suggests that institutional pressures alone are not enough to guarantee implementation success—organizational capacity and commitment remain necessary (26). The concept of resilience in hotel operations has gained increasing attention, particularly following shocks such as the COVID-19 pandemic. Resilience can be conceived as both the ability to cushion shocks and the ability to learn and transform with changing conditions (98, 99). For hotels, sustainability initiatives undertaken during mega-events can contribute to operational resilience through reducing resource dependencies, diversifying revenues, and building adaptive capacity. This study contributes to resilience theory by examining how mega-event sustainability initiatives enhance hotels' adaptive capacity and long-term viability. The analysis reveals that hotels that successfully implement comprehensive sustainability programs during mega-events often develop organizational capabilities that enable them to respond more effectively to future challenges and opportunities.

Certification systems have emerged as key mechanisms for standardizing and communicating sustainability practices in hospitality (27, 28). Industry-specific certifications like LEED have seen increasing adoption in the hospitality sector, with over 1,000 hotels globally achieving certification by 2021 (73). However, research has identified several challenges, including the proliferation of competing standards (29), varying levels of rigor (30), and questions about their effectiveness in driving genuine change vs. “greenwashing” (31). Studies by Geerts (32) and Pereira et al. (33) found that while certifications can drive operational improvements, their impact on actual environmental performance varies considerably based on implementation quality and management commitment. A critical consideration in evaluating sustainability initiatives is the well-documented gap between stated consumer preferences and actual behavior. While surveys consistently show high levels of consumer interest in sustainable tourism options, actual purchasing decisions often prioritize price and convenience (34, 35). This phenomenon, known as the intention-behavior gap or attitude-behavior gap, has significant implications for hotels investing in sustainability measures based on guest preference surveys (36, 37). The business case for hotel sustainability is further complicated by the reality that not all sustainability initiatives provide direct financial returns. While eco-efficiency measures often demonstrate clear ROI, comprehensive sustainability requires acceptance of initiatives without immediate financial benefits (8). These challenges simplistic “win-win” narratives and aligns with critical perspectives on corporate sustainability that emphasize trade-offs and competing objectives (38, 39). Research has identified various factors contributing to this gap, including: •

Price sensitivity and perceived value trade-offs (40)

This study employs a multiple case study approach, which is particularly suited for examining complex phenomena in real-world contexts where boundaries between phenomenon and context are not clearly defined (44). The case study methodology has been widely used in tourism and hospitality research to investigate sustainability initiatives (45, 46) and mega-event legacies (47, 48).

Following Eisenhardt's (49) recommendations for theoretical sampling in case study research, we selected cases that would provide both literal replication (similar results for predictable reasons) and theoretical replication (contrasting results for predictable reasons). The selection criteria included: 1.

Temporal diversity: Events spanning from 2012–2022 to capture evolving sustainability practices

Data were collected from multiple sources to enable triangulation and enhance validity (53, 54): 1.

Official documentation: Sustainability reports, legacy plans, environmental impact assessments

The analysis followed Braun and Clarke's (55) thematic analysis framework, adapted for case study research: 1.

Familiarization: Immersion in data through repeated reading

Past mega-events have implemented various sustainability measures with mixed success. Table 1 provides a comparative analysis of significant sustainability measures and their outcomes.

The proliferation of sustainability certifications in the hospitality sector reflects growing industry engagement with environmental and social responsibility (Table 2). However, evidence of direct causal links between mega-events and certification adoption requires careful examination.

Hotels implement a variety of sustainability practices for mega-events, though the extent to which these are event-driven vs. reflecting broader industry trends must be closely analyzed. The evidence suggests that mega-events serve as accelerators of pre-existing sustainability trends rather than creating entirely new practices.

Energy conservation is the most common mega-event sustainability practice among hotels, driven by environmental as well as cost-saving imperatives. London 2012 hotels attained 15%–20% energy savings by implementing LED retrofits, smart building systems, and renewable energy sourcing. Tokyo 2020 featured more advanced measures, with AI-driven energy management systems providing additional 10% savings in some properties. These advances, however, reflect broader industry trends toward energy efficiency that have been accelerated by demands and visibility created by the events.

The longevity of energy conservation actions after the event differs significantly. Those hotels that incorporated energy management into mainstream operations sustained gains, whereas those that took temporary actions tended to revert to former routines. This trend indicates that durable energy efficiency legacies depend on systematic organizational transformations instead of discrete technological initiatives.

Water conservation measures for mega-events build on those already practiced, such as linen reuse programs and low-flow fixtures, in hotels. Over 90% of London's hotels had reuse programs by 2012, though the extent to which this was event-driven adoption vs. business-as-usual practice is unclear. More advanced water conservation measures, such as greywater reuse and leak detection systems, were more obviously event-demand driven.

Hilton Tokyo Bay's 5,000-liter saving during the Games shows how events can trigger intensified monitoring and optimization of existing systems. But the relatively limited scale of these gains suggests that water conservation for mega-events is a question of intensification of normal practice rather than transformational operational change.

Mega-event waste management improvements usually highlight the most creative and long-lasting transformation of hotel operations. FIFA partnerships on waste targets led to system-wide solutions that extended beyond individual properties. Marriott's elimination of plastic straws by 2019 (76), while part of an overall corporate plan, was accelerated because of mega-event sustainability pressures.

Expo 2020 hotels' contribution of 50,000 meals reflects wider incorporation of circular economy principles that have the potential to establish long-term operational transformation. Such practices tend to continue after the event due to alignment with both sustainability objectives and operational efficiency, generating reinforcing incentives for perpetuation.

Sustainable F&B at mega-events typically prioritize local supply, vegetarianism, and waste reduction. London 2012's Food for Life certification and Paris 2024's 50% local supply commitment demonstrate how events can formalize and accelerate existing trends for sustainable hospitality practices.

The integration of sustainable F&B practices has a tendency to extend beyond the event timeline as they can help optimize guest experience and reduce costs. Hotels that develop local supply chain connections and sustainable menu options during events are likely to sustain these efforts as they become engrained in operational routines and guest expectations.

One of the most significant long-term mega-event sustainability initiative legacies in hotels is employee training programs. Beijing (77) city-wide employee training programs created long-lasting human capital that persisted well beyond the event. These initiatives have a tendency to develop organizational competencies that enable hotels to achieve sustainability performance gains by themselves well beyond the event.

However, retention of sustainability knowledge and practices is dependent to a large degree on staff turnover rates and ongoing organizational support. Hotels with formal knowledge management processes and ongoing training exhibited greater sustainability improvement persistence instigated by events.

The mega-event legacies for hotel infrastructure and destination sustainability are extremely diverse, reflecting differences in planning, implementation, and post-event management. These legacies are of particular interest to hotel operations in that they establish the context within which individual properties develop their sustainability plans. The long-term impacts of mega-events on host destinations vary considerably, reflecting differences in planning, implementation, and post-event management.

Note: The long-term impacts of mega-events on host destinations vary considerably, reflecting differences in planning, implementation, and post-event management. To enhance clarity and enable more detailed analysis, we present these findings in two complementary tables: Table 3a examines infrastructure legacies across the five cases, while Table 3b specifically analyzes the implications for hotel operations and sustainability outcomes.

This study contributes theoretically by building on Preuss's (15, 87, 88) legacy frameworks and the adaptive systems literature. Specifically, it examines how event-time sustainability efforts catalyze longer-term adaptive capacity in hotels, thus extending resilience theory. The empirical findings challenge and enrich these frameworks by emphasizing the importance of sector-specific implementation mechanisms and organizational routines.

Our findings contribute to several theoretical discussions in tourism and event management literature. First, we extend legacy theory by demonstrating how sustainability initiatives create multi-dimensional impacts that transcend traditional economic and infrastructural outcomes (88). The cases reveal that environmental legacies are deeply intertwined with social and economic dimensions, supporting integrated approaches to legacy planning (13, 89).

Specifically, this study advances legacy theory by identifying the mechanisms by which hotels translate transient event pressures into resilient organizational capabilities. The results suggest that successful legacy creation is not only about initial adoption of sustainable practices, but also creating organizational routines, systems of knowledge, and stakeholder relations that contribute to continuous improvement. This result extends Preuss's (15) legacy conceptualization to emphasize the importance of adaptive capacity in predicting whether event-induced changes are sustained and evolve.

Second, our analysis provides empirical evidence for institutional theory perspectives on sustainability adoption in hospitality (25). Mega-events create coercive pressures (regulations, requirements), normative pressures (industry standards, certifications), and mimetic pressures (best practice adoption) that accelerate sustainability implementation. However, the variation in outcomes across cases suggests that institutional pressures alone do not guarantee successful implementation—organizational capacity and commitment remain critical factors (26).

The study illustrates that hotels respond to institutional pressures in different ways based on their existing capabilities, resource constraints, and strategic agendas. Hotels that already have sustainability practices can leverage mega-event pressures to advance improvements, but inexperienced hotels might struggle to implement major changes within event timeframes. The finding contributes to institutional theory by demonstrating the requirement of organizational readiness for moderating institutional impacts.

Third, the study highlights the complexity of the business case for sustainability in hospitality. While eco-efficiency measures often demonstrate clear ROI, our findings support Melissen et al.'s (8) argument that comprehensive sustainability requires acceptance of initiatives without direct financial returns. This challenges simplistic “win-win” narratives and aligns with critical perspectives on corporate sustainability (38, 39).

The concept of “sustainability-enabled resilience” is a concept emerging from our research, and its implications are that hotels adopting overall sustainability strategies in the context of mega-events build adaptation capabilities that pay off well beyond the life of the event. Specifically, this contribution to hospitality resilience theory illustrates how sustainability strategies and measures can be at once ends and means of building organizational resilience.

The hospitality industry has been increasingly adopting green technologies, though significant implementation challenges remain (96). Olympic Agenda 2020 has further emphasized sustainability as a core pillar for mega-events (97).

Our findings must be interpreted in light of the well-documented intention-behavior gap in sustainable tourism (34). While 73% of tourists express preference for sustainable hotels (3), actual booking behaviors often prioritize other factors. Hotels investing in sustainability based on stated preferences may overestimate demand, particularly for measures that increase costs without enhancing guest experience.

This gap manifests differently during mega-events. Event attendees may be less price-sensitive than typical tourists, potentially reducing barriers to choosing sustainable options. However, convenience factors (proximity to venues, availability during peak periods) may override sustainability considerations. Hotels must therefore frame sustainability initiatives not solely as responding to guest demands but as fulfilling broader stakeholder expectations and regulatory requirements.

The evidence is directed to the business case of sustainability in hotel operations of mega-events as complicated. Since eco-efficiency efforts are likely to reflect clear ROI by way of reduced operating costs, our findings substantiate Melissen et al.'s (8) argument that serious sustainability in hotels must embrace actions without manifest monetary benefits. This challenges naive “win-win” arguments and agrees with critics' arguments regarding corporate sustainability (38, 39). Our analysis reveals that mega-event sustainability initiatives encompass more than eco-efficiency measures. Environmental sustainability includes investments in renewable energy infrastructure, biodiversity conservation, and circular economy practices—many without immediate financial returns. Social sustainability dimensions include: These findings reiterate the importance of explicitly anchoring sustainability legacies within hotel operations—highlighting how hotel-specific constraints and incentives shape long-term outcomes. •

Workforce development: Training programs, fair labor practices, career advancement opportunities

The variation in outcomes across cases underscores the importance of governance structures and accountability mechanisms. London 2012's independent oversight body provided credibility and enabled adaptive management. Conversely, Qatar 2022's disputed carbon-neutral claims illustrate how inadequate transparency can undermine legitimacy, regardless of actual achievements.

This finding supports calls for standardized reporting frameworks and third-party verification in event sustainability (91). The adoption of ISO 20121 (sustainable event management) and alignment with GRI standards represents progress, but enforcement remains inconsistent. Future events must balance ambitious targets with credible measurement and reporting to avoid greenwashing accusations.

Our analysis reveals that sustainability legacies are neither uniformly positive nor represent clear “win-win” scenarios. Several factors complicate outcomes: 1.

Temporal dynamics: Short-term gains may not translate to long-term benefits without continued investment

For event organizers and policymakers: •

Integrate sustainability planning from bid stage, not as add-on

This study examined how mega-events influence sustainability practices in the hotel sector, revealing complex patterns of adoption, implementation, and legacy. While events can catalyze significant improvements in environmental and social performance, outcomes depend critically on governance structures, stakeholder commitment, and post-event management. The findings challenge simplistic narratives of universal “win-win” outcomes, instead revealing trade-offs between different sustainability dimensions and stakeholder interests.

The research contributes to theoretical understanding of legacy creation, institutional pressures in sustainability adoption, and the evolving business case for comprehensive sustainability beyond eco-efficiency. Practical implications include the need for integrated planning, transparent accountability mechanisms, and recognition that meaningful sustainability requires accepting some initiatives without direct financial returns.

Future research should employ longitudinal designs to track legacy evolution, examine differential impacts across stakeholder groups, and investigate how emerging regulations (e.g., CSRD, mandatory climate disclosures) influence event and hotel sustainability practices. As the climate crisis intensifies and social inequalities persist, the imperative for genuinely sustainable mega-events—and the hospitality infrastructure supporting them—will only grow stronger.