  Studies of mid-infrared space interferometer concepts in the USA and in
Europe have converged on a single architecture. We address the question of how
the US and European communities could collaborate to advance technology efforts
leading to a future space mission. We present the current state of the art in
nulling interferometry, as demonstrated at ambient temperature and pressure in
the lab, and outline required steps to demonstrate its performance under space
conditions. Design studies of a cryogenic optical test bench under vacuum have
already been carried out. We highlight pre-conditions and constraints of a
collaborative effort, foreseeable practical and administrative challenges, and
possible strategies to meet those challenges.
