1. Patients over 18 years of age, assessed as fit for routine colonoscopy

2. Patients attending for screening or surveillance colonoscopy meeting the following criteria:

* Polyp surveillance with at least 3 adenomas or 1 adenoma\>10mm at previous colonoscopy

* Surveillance post colorectal cancer resection

* Screening with positive faecal occult blood test

Discard:Characterisation of Colonic Polyps in Vivo