The effects of the preparation method (combustion and incipient wetness) and Co loading (1-5 wt%) on the structure, redox, and morphological properties of the Co/CeO2 system were probed by X-ray diffraction, X-ray photoemission spectroscopy, scanning electron microscopy, CO and H-2 chemisorption and temperature-programmed desorption measurements. Synthesis route and Co-loading control the structure and morphological properties, markedly affecting the reactivity of the Co/CeO2 system in the Fischer-Tropsch synthesis (FTS) reaction (TR = 250 degrees C; P-R = 20 atm). Both metal-support interaction(s) and Co dispersion control the strength and relative concentration of CO and H-2 adsorption sites enabling marked differences in the specific site-time-yield of the various catalysts. (c) 2005 Published by Elsevier Inc.