We develop a general framework for assessing the stance of office prices with respect to their fundamentals. Applying the model to France, we show that constrained office supply and low interest rates mainly explain the high level and upward trend of office prices in recent years. Nonetheless, we find that the office market is only slightly overvalued in France in the late year 2017, between 0% and 10%. Lastly, we stress the usefulness of the framework for financial stability purposes and we evaluate the effect of the Brexit on office prices in the Paris Region.