PE sponsors build entire compliance programs around identifying and preventing any violations or mistakes that could draw the ire of the SEC or investors. Prevention is only half the battle, however, as sponsors must take a series of steps if an issue results in an investor complaint. Sponsors need to promptly acknowledge and address the displeasure of the investor; thoroughly investigate the complaint; and correspond with the investor in a way that addresses the concern and mitigates future harm. This two-part series identifies common issues in how PE sponsors address investor complaints and provides actionable guidance for improving those efforts going forward. This second article outlines considerations and guidance for investigating a complaint, as well as tips for communicating with the investor in question. The first article established the parameters for what qualifies as an investor complaint, along with how sponsors should document the entire complaint process and avoid common mistakes along the way. For more on addressing complaints, see “Best Practices for Fund Managers to Mitigate Litigation and Regulatory Risk Before Terminating Employees” (Feb. 9, 2017); and “How Can Private Fund Managers Mitigate the Reputational Harm of Whistleblower Complaints?” (Oct. 8, 2010).