The aim of this paper is to examine the links between developed environmental innovations and the competitiveness of firms. It seeks answers to the question: Are the developed environmental innovations associated with the improved or impaired competitiveness of firms? In addition, it explores how competitive advantage is created along the innovation process. This will be done by comparing the successful and unsuccessful green innovators. The empirical evidence is based on the longitudinal dataset gathered from 128 Finnish firms which have developed one or more environmental innovations. The data covers nine years from 2002 to 2010. This study provides two contributions to academic literature. First, it deepens the existing knowledge of how environmental innovations are associated with competitive advantage. It identifies the types of competitive advantages as well as potential disadvantages along the innovation process. Second, this study demonstrates how the competitive advantage was enhanced along the successful innovation process. Copyright © 2013 John Wiley & Sons, Ltd and ERP Environment