IRIDRA is a small (6 associated) engineering and consulting company, born in 1998 and based in Florence. IRIDRA realises any activity connected with planning, design, and work supervision for sustainable water management, sanitation, and climate change adaptation and mitigation. It is specialised in the fields of nature-based solutions, green-blue infrastructure, sustainable drainage systems (SuDS), ecosystem services, with a particular focus on Constructed Wetlands for wastewater treatment and reuse. IRIDRA members are actively collaborating since about 20 years with the main national environmental organisations (Legambiente, Ambiente e Lavoro, etc.) and relevant associations of the water sector like the International Water Association. IRIDRA is also one of the founding companies of Global Wetland Technology, a consortium of 10 companies which have been operating for almost 20 years in wastewater treatment and water pollution control by Constructed Wetlands. Finally, IRIDRA is member of the Constructed Wetland Association, and of the Sustainable Sanitation Alliance network. IRIDRA took part in several research projects such as FP5 Swamp, MEDA Zer0-M, ENPI-CBCMED SWMED, FP7 Nawatech, FP7 OpenNESS. With the writing of more than 40 peer-reviews publications, 100 extended abstracts, several guidelines, and book chapters, IRIDRA has given a relevant contribution to the worldwide dissemination of nature-based solutions.