Colon cancer is the second leading cause of cancer death in the United States. Each year, almost 140,000 people are diagnosed with colon cancer, and 50,000 people die from the disease1. Diagnosis and treatment often require invasive procedures, including colonoscopies and surgery. Less invasive treatments such as chemotherapy cause unpleasant side effects. We turn to synthetic biology to develop a better colon cancer therapy. An ideal cell-based therapy would have two significant components: a way to kill cancer cells, and a way to specifically target them. In our quest to find a way to specifically target cancer cells, we found that the problem of controlling a cell’s interaction with its physical environment extended beyond cancer therapy into a myriad of biological contexts. Harvard iGEM 2015 focuses on building a platform for controlling specific bacterial adhesion in a variety of biological settings, including colon cancer therapy.