Gabrielli D., Jona-Lasinio G., Landim C. Onsager reciprocity relations without microscopic reversibility (18K, ApsTeX) ABSTRACT. In this paper we show that Onsager--Machlup time reversal properties of thermodynamic fluctuations and Onsager reciprocity relations for transport coefficients can hold also if the microscopic dynamics is not reversible. This result is based on the explicit construction of a class of conservative models which can be analysed rigorously.