World Environment Day is a reminder that achieving a more sustainable future requires more than ambition. It requires infrastructure that can support resilient communities, drive economic development, and withstand growing environmental challenges. Yet building sustainable infrastructure is not only about what governments invest in, but also how those investments are planned, delivered, and monitored. 

Recent findings from CoST Ecuador highlight why transparency and accountability are essential to ensuring infrastructure projects deliver the environmental and social benefits they promise. Through its Independent Review, CoST Ecuador examined major public infrastructure projects and found that while investments in areas such as sanitation and public services have the potential to improve quality of life and environmental outcomes, weaknesses in planning, project oversight, and information management can undermine those benefits.

In several cases, projects experienced delays, design modifications, or implementation challenges linked to outdated studies, changing local conditions, and gaps in project information. These findings reinforce an important lesson: sustainable infrastructure cannot be achieved through investment alone. It depends on reliable data, effective oversight, and the ability to identify risks before they become costly failures. 

This challenge is not unique to Ecuador. Around the world, CoST members are working to strengthen the transparency and accountability needed to support more sustainable infrastructure systems. 

In Vietnam, CoST has contributed to discussions on green and sustainable infrastructure through the Green Cities Infrastructure and Energy programme (GCIEP), helping to advance conversations on how transparency can support more resilient and environmentally responsible investment decisions. 

In Malawi, CoST has explored how climate finance can be tracked and monitored more effectively, helping governments and citizens better understand whether investments intended to support climate resilience are delivering results. Through the use of the Infrastructure Transparency Index and broader work on public infrastructure disclosure, CoST Malawi is demonstrating how access to information can improve accountability for infrastructure spending and outcomes. 

Across Latin America, CoST members have contributed to regional dialogues on sustainable infrastructure, emphasising the importance of transparency, participation, and accountability in ensuring that infrastructure investments respond to both environmental and community needs. Similar conversations are taking place across Africa, where rapid urbanisation and growing infrastructure demands make sustainable and transparent decision-making increasingly important. 

These examples point to a broader reality: sustainability and transparency are not separate goals. Infrastructure projects can only deliver lasting environmental and social benefits when decision-making processes are open, project information is accessible, and stakeholders are able to engage meaningfully throughout the project lifecycle. 

As governments seek to address climate change, strengthen resilience, and meet sustainable development objectives, transparency must be recognised as part of the solution. Better information helps decision-makers respond to changing circumstances, enables citizens to hold institutions accountable, and creates the trust needed to support long-term investment. 

This World Environment Day, the conversation should not only focus on the infrastructure we need to build, but also on the systems that ensure it delivers value for people and the planet. Sustainable infrastructure begins with transparency.