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This paper aims to investigate the interaction effects among market concentration, profitability, research and development (R&D), and advertising in Iran’s manufacturing sector. For this purpose, the quarterly data on Iran’s manufacturing sector was gathered in ISIC (International Standard Industrial Classification) codes, then the interaction effects of structure, conduct and performance was analyzed for industrial groups by Vector Error Correction Models (VECM) over the period 1996-2007. The results show that innovation and R&D are related to concentration, profitability and advertising within industries in the long-run. On the other hand, concentration and profitability explain 50% of variations in innovation and R&D; however, profitability, as a performance indicator, has the most effect on R&D activities in long run. Therefore, our finding is in line with Chicago-U.C.L.A theory.