Many nonprofit centers I’ve visited do a lot to reduce their carbon footprint, from putting in super-efficient HVAC systems and bio-walls to replacing your trash-can with a recycling bin. Since approximately 20% of office waste is organic matter, the next step for many groups is to start an office composting program. Both centers I’ve worked out of, the Thoreau Center for Sustainability in San Francisco and The Alliance Center in Denver, have run successful composting programs for years. Here are some tips your space.