Global epidemics of infectious diseases are increasing in frequency and severity. Diagnostics are needed for rapid identification of the cause of the epidemic to facilitate effective control and prevention. Lessons learned from the recent Ebola virus and Zika virus epidemics are that delay in developing the right diagnostic for the right population at the right time has been a costly barrier to disease control and prevention. We believe that it is possible to accelerate and optimise diagnostic development through a five-pronged strategy: by doing a global landscape analysis of diagnostic availability worldwide; through strategic partnerships for accelerating test development, in particular with vaccine companies to identify novel diagnostic targets; by creating and sharing repositories of data, reagents, and well characterised specimens for advancing the development process; by involving key public and private stakeholders, including appropriate regulatory bodies and policy makers, to ensure rapid access for researchers to diagnostics; and last, by fostering an enabling environment for research and access to diagnostics in the countries that need them. The need is great, but not insurmountable and innovative and faster development pathways are urgently required to address current shortfalls.