Despite the great importance attributed to intellectual capital (IC) in the past two decades or so, its measurement and management have remained elusive, mainly because of inappropriate prior models of IC measurement. The purpose of this study is, therefore, to make adjustments to an existing model, the Value Added Intellectual Coefficient (VAIC), and to present an adjusted-VAIC model to measure IC. We tested our new model on data from 10 emerging and developed world markets and obtained more consistent results than prior studies. Our results indicate a significant positive relationship between IC and its components (human, innovation and physical capitals) and firm performance. Therefore, the adjusted-VAIC model can be used with confidence to measure IC. Our study has important implications for both academia and industry concerning the measurement of IC.