This document summarizes evidence of voluntary transactions for ecosystem services including water, biodiversity, voluntary carbon, and forest carbon. It provides examples of specific programs and transactions around the world. For water transactions, it notes over $20 billion total has been transacted through over 200 programs. For biodiversity, it estimates $2.4-4 billion annually is transacted protecting over 187,000 hectares. Voluntary carbon transactions in 2010 totaled over $400 million for over 130 million tons of CO2. Forest carbon programs in 2009 generated over $149 million from over 200 projects across over 2 million hectares. The document provides several case studies as illustrations.