Chris van Swaay is a biologist who has specialized in the ecology and conservation of butterflies in The Netherlands and the rest of Europe. 

Since 1990 he has co-ordinated the Dutch Butterfly Monitoring Scheme, in close collaboration with Statistics Netherlands (CBS). In this citizen science monitoring scheme he co-ordinates the work of more than 1000 volunteers. 

At a European level he was leading author on some of the major overviews on butterflies in Europe, including the Red Data Book of European Butterflies, published by the Council of Europe in 1999, the book describing Prime Butterfly Areas in Europe in 2002 and the Red List of European Butterflies in 2010. 

Another important line of work at the European scale is performed via Butterfly Conservation Europe (BCE). Together with other partners of BCE he developed European indicators on Grassland butterflies as well as a European Butterfly Climate Change Indicator.  

Next to this he has performed many smaller research and consultancy projects for Dutch Butterfly Conservation, both in the Netherlands and elsewhere in Europe. This work included for example the Red List of Dutch Butterflies and several species protection plans.