The growing complexity of investment decision-making has increased the potential value of advice from a financial professional. Past research provides only a very partial answer to the question of whether professional financial advice leads to better investment practices and results. In this chapter, we review findings in the existing research literature, detail ‘best practice’ research approaches for drawing confident conclusions regarding causal influences, and provide an example of such an approach using data from the 2007 Survey of Consumer Finances. Our results suggest that the benefits of financial advice may be overstated in the absence of methodological rigor.