The importance that intangible assets have had during the last years due to their potential to create value and develop sustainable competitive advantages, has lead firms to review the way in which they are managed and measured to find some features that differenciate from the competitors; because of their source of information and knowledge they are called intellectual capital. In a global economy, the effects of the financial phenomena occurring in one country are reflected in others, affecting the results of the companies quoting in the stock markets. The subprime crisis had its origin in the North American mortgage market, and spread until affecting most economies of the world. During it, Mexican Stock Exchange (MSE) lost approximately 24% of its market value. The aim of this non-experimental quantitative, co-relational-descriptive and longitudinal research, made with the firms quoting in the communications and construction sectors of the Mexican Stock Exchange during the period 2005-2009, is to compare an absolute measure -intellectual capital calculated by the Market Value Added method-and a relative measure -the relationship Price/book value-because in crisis times investors prefer companies that intensively use intangible assets or those that base their performance in fixed assets. The information shows that there is no co-relation between the intellectual capital calculated by the Market Added Value method (VAM) and the relationship Price/book value during the period studied, due to the increasing dissociation between the market value of the shares which emphasizes the importance of intangible assets, and their book value, which almost remains constant because of the accounting norms applied.