Page contents Page contents Buying green handbook The handbook is the European Commission's main guidance document to help public authorities buy goods and services with a lower environmental impact. It is also a useful reference for policy makers and companies responding to green tenders. Buying green handbook Guidance for bio-based products in procurement This guidance is to help public buyers and other interested parties to obtain more information about bio-based products (wholly or partly derived from materials of biological origin) and to consider innovative bio-based products alongside other products when making their buying decisions. The guidance includes a handbook for trainers and factsheets on specific products. Guidance for bio-based products in procurement