As a marketer, you face many dilemmas: Should you focus on brand-building or sales-focused marketing? Should you use rational or emotional ads? How should you evaluate different media channels against each other? Most experts would like you to believe that there is one right answer to these questions. Unfortunately, the reality is more complex. The correct answer for your specific situation requires an overall understanding of customer psychology.   After years of research and working with marketers, Erik Modig and Martin Söndergaard developed the Influence Matrix, a new way to make sense of today's many marketing theories. The practically applicable framework captures the insights from the 100 most popular books and the 300 most cited peer-reviewed articles in marketing, communication, and decision-making. By applying it, you will be able to identify and tackle your main marketing challenges, taking your marketing strategy and communication tactics to the next level.