Microscopic images of haematological cells are now routinely photographed using digital cameras. Advances in technology mean that the quality of such digital images can now approach that viewed through a microscope. At the same time there is an emerging appreciation that such images can be used in many roles: digital images are now being used to construct digital 'virtual slides', or are being employed together with cell recognition systems for morphological screening. Additionally, an Internet-based viewing systems allow access to on-line annotation, as well as real-time data gathering and feedback. The process of viewing digital images differs from the viewing of glass slides through a microscope; however, such images can provide diagnostic equivalence, and have an emerging role in areas such as education, quality control and continuing professional development. This review explores some of the present strengths, weaknesses and future applications of digital imaging in haematology.