: Minutiae features extracted from finger images are widely used for automated fingerprint recognition. The conformance of minutiae templates to standardised data interchange formats and the interoperability of minutiae extraction and comparison subsystems from multiple suppliers are important to prevent proprietary lock-in. Based on the work performed within the European research project on minutiae template interoperability testing, this paper summarises conformance and interoperability issues that have arisen and proposes solutions. 1 Motivation for minutiae template interoperability testing Most fingerprint systems compare minutiae, i.e. characteristic points of the dermal ridges, rather than full fingerprint images. A minutia is characterised by its location, the direction of the tangent to the ridge skeleton at this point, and its type (ridge ending, ridge bifurcation, or other). To help ensure interoperability between minutiae extraction and comparison subsystems from different ...