Purpose - The purpose of this paper is to provide a review of recent progress in the development of medical microrobots. Design/methodology/approach - The paper first considers some of the critical aspects of medical microrobot design and then illustrates the present state of development through examples of prevailing research. Findings - This paper shows that medical microrobot developments are at an early stage and involve a disparate family of technologies and disciplines, such as MEMS, nanotechnology, biomimetics and hydrodynamics. Critical design issues include power sources, propulsion and location, and many different schemes have been proposed. These are the topic of a growing body of academic research. Originality/value - This paper provides a detailed insight into the present-day state of medical microrobot technology and development.