Many existing studies of office markets involve an office rent adjustment process, incorporating demand and supply side factors. This paper develops an empirical model of the Paris office market using four overlapped equations of key variables: take up, rental value, capital value, and new construction. Some of the equations are specified in an ECM (Error Correction Model), which provides information on both the long-run relationship and short-run dynamics. Two theoretical concepts have been created and used within the model framework: (i) a market pressure variable which reflects the tightness of the market: a construct of take-up, total stock and new construction; (ii) the theoretical capital value is based on an asset valuation method: establishing the expected value that ëshould' be observed in the market given the underlying fundamentals. Within the model system: take up is driven by macro variables and changes in office rent, which along with new construction depend on macro and real estate variables and capital value is based on macro variables, market pressure and theoretical capital value. Therefore, a divergence of the observed capital value from the theoretical capital value, would suggest disequilibrium in the market. The empirical results of the overall framework are appropriate to explain the bubble phenomenon in the early nineties, the peak observed in the millennium and the downturn of the Paris office market in line with the recent economic slowdown.