I've recruited for financial services companies for years and can give some context on what Vanguard's behavioral round actually tests, because the company's culture is genuinely distinct from typical tech companies.
Vanguard is crew-owned (technically a mutual company structure, owned by its fund shareholders). This isn't just marketing. It shapes how they think about employee behavior and values. The behavioral interview reflects that.
Recurring themes I've seen in Vanguard behavioral loops: Integrity / doing right by the client. They will almost certainly ask something like: "Tell me about a time you had to make a decision that was right for the customer even though it was harder for your team or you personally." This is not throwaway. Vanguard's entire brand is "we're the fiduciary who doesn't rip you off." Live that in your answer. Collaboration over heroism. They do not want cowboy engineers or lone-wolf deliverers. If your best STAR story is "I stayed up all night and fixed it myself," that might not land the way you think. Reframe to show how you pulled people in, communicated, got alignment. Long-term thinking. Most Vanguard employees stay a while. They're not a startup. Questions about where you see yourself in 3-5 years are taken seriously, and answers that signal you're looking for a 2-year sprint before moving on don't play well. Handling complexity or ambiguity. Pretty standard, but they ask it through the lens of large, slow-moving systems. "Tell me about navigating a large cross-functional change" style.
Common questions I've seen candidates come back reporting: "Tell me about a time you had to push back on a stakeholder or leadership decision." "Describe a situation where you had to balance short-term pressure with long-term quality." "How do you ensure your work is aligned to what the end client actually needs?"
Prepare 6-8 solid STAR stories and tag them. The behavioral round is usually 45-60 minutes, two or three questions with follow-up probing.
One more thing: Vanguard's culture is genuinely quieter and more deliberate than a lot of tech shops. People who come across as frenetic or who fetishize speed for its own sake tend to get dinged.