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Provided by ENVIR Advocaten

Public law boutique ENVIR Advocaten exclusively focuses on providing its clients with public law advice and support. 

Based in Amsterdam, ENVIR was founded in 2014 by partners Marieke Kaajan and Fleur Onrust. ENVIR opened its Leeuwarden office in 2019. Derek Sietses heads the Leeuwarden office.

ENVIR is recognised in the field as the specialist in environmental law, including nature conservation, (sustainable) energy, and zoning and planning. ENVIR is active in the renewable energy sector, including wind and solar. In addition, ENVIR advises on general administrative law issues and procedures (eg administrative enforcement and subsidies) and assists several corporate law firms in large M&A deals on administrative law, environmental and zoning aspects, such soil and groundwater contamination.

Clients are mainly companies and the (semi-)public sector, operating or involved in various sectors, such as energy (including renewable energy generation and wind energy), climate change, (chemical) industry, aviation, real estate, infrastructure, hospitality and health care.

The lawyers of ENVIR publish and teach frequently on several environmental and administrative law issues in legal periodicals and with renowned legal knowledge institutions.


Provided by ENVIR Advocaten

Derek Sietses


Provided by ENVIR Advocaten


Climate Change

EU Law

Energy & Natural Resources

Health Care



Leisure & Hospitality

Public Law

Public Law – Planning & Environment

Public Law – Transactional

Real Estate