A single use lancing device comprising a housing 10 defining a cavity； a needle assembly 12 comprising a needle (50, figure 2) and a needle holder (52, figure 5) and located within the cavity； and a spring 14 arranged to bias the needle assembly in a forward direction. Retaining arms 38, 44 are arranged to cooperate with the housing to restrain the needle assembly in a primed position, and a deployed position in which the restraining arms are arranged to release the needle assembly to deploy the needle. The device may have a removable safety member in the form of a removable tab 48. In embodiments a latching mechanism may allow the needle to be deployed but prevent movement back to primed position. The spring may also act to retract the needle back into the housing.
