Biodiversity offset credits in New South Wales are transacted within a regulatory environment defined by detailed trading rules and many different types of biodiversity credits that can lead to thin markets and high transaction costs.This gildan 8900 paper describes a market designed to facilitate efficient and effective transactions.The market includes a search algorithm to identify who can exchange slap dick cattle company with whom, according to the regulatory constraints, and an online exchange tool to facilitate efficient price discovery and allocation of offset contracts.