This paper examines the role of marketing effectiveness in the relationship between innovativeness dimensions (e.g., product, market, process, strategic, and behavioral innovativeness) and firm performance. Data were collected via structured questionnaires from 112 firms operating in Turkey and analyzed through hierarchical regression analysis. Findings indicate that different dimensions of innovativeness have different effects on marketing effectiveness and firm performance. The results also support the mediating role of marketing effectiveness in the relationship between firm performance and product and strategic innovativeness dimensions. In addition, several firm characteristics (e.g., firm size, share of foreign capital) are shown to moderate the effects of innovativeness dimensions on marketing effectiveness and overall firm performance.