<p>Human heart valve homografts, usually donated after death, are banked worldwide to facilitate reconstructive cardiac surgery, which is a necessary procedure to repair both congenital and acquired cardiac defects. Donations of substances of human origin carry a risk of transmitting infection to recipients. As a result, several different precautions are taken to minimise this risk. Testing the tissue product for possible contamination, and carrying out decontamination of the tissue (often through the use of an antibiotic cocktail) are two of the procedures performed routinely in tissue establishments to minimize the risk of transplantation associated infections. This area of clinical practice does not have an established external quality assessment (EQA) Scheme. This report describes an initial pilot scheme of an EQA to investigate the microbiology testing of heart tissue banking, a collaboration between the Scottish National Blood Transfusion Service (SNBTS) and UK National External Quality Assessment Service (UK NEQAS) for Microbiology. The results highlight the differences in practice between different tissue banks, further supporting the need for setting up an EQA on a regular basis and the need to produce a best practice method document to attempt harmonisation of the testing.</p>