Although there are many drugs available for the treatment of IBD, most patients do not respond long-term to any one drug. One possible reason is that the condition we call “IBD” likely represents many distinct diseases, rather than simply just ulcerative colitis and Crohn’s disease, and each subtype may require a different treatment. Here we will address this problem by using a suite of state-of-the-art laboratory techniques that will allow us to study the genetic instructions (RNA) of thousands of individual cells sampled from the intestines of patients with IBD. Using bioinformatic methods, we will use this information to classify IBD into different diseases, which may help us to determine how best to treat each subtype. We also hope to discover new molecules that are involved in causing IBD, an important first step to developing new treatments for IBD