How to help developer gain agile mindset One of the developers on my Scrum team comes from a less agile team than ours. The PO told me that this developer doesn't like to collaborate with the other developers and the PO, and also that he doesn't have good knowledge of our engineering practices like small branches and PRs, etc. So he is like a bit of an island inside the team. It's a vicious circle because he doesn't collaborate, so he doesn't learn. As Scrum Master, what is the best way to tackle this? Should I run a retro and hope the team raises this topic and discusses it?

A good place to start would be to try and work out what is motivating this behaviour.

Is it that they don't feel these working practices have value?

Maybe they are introverted and feel uncomfortable when collaborating?

Once you have a feel for their motivation it will hopefully be easier to work out an approach.