In malaria his early work showed that single proteins affinity purified from the parasite could be used to immunise against blood stage infection. One of these proteins is a member of the RH family that has recently seen resurgence in interest as vaccine candidates. The second is the well-known merozoite surface protein 1 (MSP1) which he characterised extensively. He has described a range of parasite proteins involved in invasion and colonisation of erythrocytes, particularly proteins located on the parasite surface and in apical secretory organelles.

His work has ranged from molecular studies in the laboratory to community studies in human populations in malaria endemic areas. At the ‘molecular’ end of this spectrum this work covers genetic, protein structure and function, and cell biology studies.