Harold Brommer finished in 2005 his PhD thesis entitled 'Towards detection of functional failure of equine articular cartilage: the metacarpophalangeal joint under scrutiny.' He is involved into the research lines 'Regenerative Medicine, Stem Cells and Cancer' and 'Bioveterinary Medicine' within the strategic theme 'Life Sciences.' Within the line 'Regenerative Medicine, Stem Cells and Cancer' he focusses on equine joint disease and more specifically on aspects of early degenerative changes of articular cartilage and follow-up of healing after (surgical) repair. He closely collaborates with PdD-students and with the Finnish research group 'Biophysics of Bone and Cartilage' in Kuopio. Within the line 'Bioveterinary Medicine' he supervises research in the field of back disorders in the horse. He also collaborates with the farriers of the Faculty of Veterinary Medicine on the development of 3-D printed horseshoes.