The genesis of the biodefense system of the Polish Armed Forces, created according to the NATO standards, was discussed in this paper. Special attention has been given to cooperation (initiated in 1994) between the Military Institute of Hygiene and Epidemiology (MIHE) and the U.S. military research institutions responsible for chemical and biological defence, including the Edgewood Research Development and Engineering Center and many others. The collaboration resulted in the acquisition of significant knowledge and experience. Personnel of the MIHE has been trained in the USA to detect and indentify biological agents, several scientific conferences have been organized, and a number of joint field and laboratory exercises covering biological agent detection and identification have been conducted (e.g. Dugway Proving Ground, USA). Thanks to the collaboration, the first Biosafety Level‑3 (BSL 3) laboratory has been established in Poland and a network of military Biological Reconnaissance Teams, operating in the whole territory of Poland, has been formed. Moreover, a special reconnaissance unit designated for overseas missions (it took part in the Operation Iraqi Freedom) was created. The Biological Threats Identification and Countermeasure Centre of the MIHE has become a part of the international network (such as the NATO laboratory network, US DoD‑GEIS, EBLN, EVD‑LabNet) responsible for monitoring and identification of biological agents.