I went through the BMS behavioral round twice in the last year, once for a digital team role and once (more recently) for a cross-functional PM-adjacent position. Here's what I've noticed about how they run these.
BMS has five public values: Passion, Innovation, Urgency, Accountability, and Inclusion. You can find them on their site. In practice, the behavioral round felt organized around patient focus, collaboration across functions, and dealing with ambiguity. Every question I got mapped back to one of those three things.
Questions I got asked: Tell me about a time you had to make a decision without complete information. Describe a situation where you worked with a team that had very different priorities than yours. Give me an example of a time you advocated for a patient-centered outcome when there was pressure to go another direction. Tell me about a failure. What did you do after? How have you handled a project where the requirements changed significantly mid-flight?
The "patient-centered outcome" question was the one that caught me a little off guard. If you're coming from pure tech (not healthcare), you need to think about how your work ultimately connects to end users who might be sick, vulnerable, or dealing with something serious. They want to hear that you take that seriously, not in a scripted way, but genuinely.
Format: 60 minutes, one interviewer, STAR method throughout. Mine used a structured rubric (I could tell from how she probed). She asked follow-ups after every story: what would you do differently, what was the result, how did others react.
I also found the round more emotionally engaged than typical tech behavioral interviews. The interviewer shared why she cared about the mission. It felt different. I left the call actually wanting to work there, which doesn't happen often.
One warning: don't over-polish your answers. They're good at spotting canned responses. I had better results when I told a story that didn't end perfectly and just explained what I learned.