Europe has ambitious laws and policies to protect air and water, to promote the circular economy, prevent waste generation, raise recycling rates, and safeguard nature. Implementation is key to achieving environmental objectives, and meeting obligations as defined by the EU environmental legislation. In 2016, the Commission undertook to report regularly on the state of the implementation of EU environmental legislation. It launched the Environmental Implementation Review (EIR), a tool that helps Member States address systemic obstacles to environmental integration by identifying the causes behind poor implementation and by sharing good practices through peer-to-peer support. This factsheet summarises the progress achieved and the remaining challenges identified for Portugal in the third EIR package published in September 2022. Portugal hosts a rich biodiversity both on land and in its marine environment. The implementation of EU environmental law and policy supported by significant EU funding has contributed to preserve and to improve the environment in Portugal. Nevertheless, overall environmental implementation and enforcement continues to be a challenge for Portugal.