For travelers particularly interested in wildlife and environmental conservation this site currently promotes 150 programs in 40-plus countries. Its eye-catching possibilities include helping at wildlife sanctuaries, participating in marine and sea-turtle conservation and assisting with ecological research, though its portfolio also extends to teaching, healthcare and community projects. Founded in 2006, GoEco acts as an intermediary between volunteers and projects and provides pre-departure guidance and support during placements. Programs vary quite a bit in price, length and inclusions, so comparisons are important. The site's strong conservation emphasis makes it particularly appealing to travelers seeking hands-on involvement in wildlife or environmental projects.

Read more in my post 5 of the Top Websites for Voluntourism.