The IAHR Young Professionals Hydro-Environment Challenge seeks to promote international and interdisciplinary collaboration among young professionals and academics working at institutions across the globe in the hydro-environment field. It is an open contest, hence any kind of young professional profile working on any of the IAHR main themes is welcome to take part in the initiative. Several case studies will be assigned to the participating teams who, after a period of web-based collaborative engineering work, will present their project outcomes during an IAHR webinar. Project stakeholders and senior IAHR members will be involved during the design and mentoring of the case-studies. A jury made up of senior IAHR members and representatives from partners in academia and industry will evaluate the teams.