Due Diligence Questionnaire (DDQ)

A Due Diligence Questionnaire, commonly called a DDQ, is a structured set of written questions that an investor or their advisor sends to a fund manager or investment firm. The answers cover everything from ownership structure and key-person policies to compliance history, valuation practices, and cybersecurity protocols. Because the questions follow a consistent format, allocators can compare responses across multiple managers side by side.

For wealthy families evaluating private funds or separately managed accounts, the DDQ is often the first deep look under the hood. It surfaces operational risks — back-office failures, conflicts of interest, auditor changes — that performance numbers alone would never reveal. As families move up in sophistication, described in resources like wealth at the $100 million level, operational due diligence tends to become as rigorous as investment due diligence.

A common confusion is treating a completed DDQ as a final approval rather than a starting point. The document is self-reported, so follow-up calls, reference checks, and on-site visits remain important. A DDQ answered carelessly or evasively is itself a meaningful data point about how a manager operates.