Not currently working in the professional services world, but have in the past. We had great retention and attribute it to:

- Never being asked to time track. Projects were billed in quarterly increments based on impact, not number of people working on them. This made swapping people based on their speciality easy.

- Being paid above market rate.

- Getting lots of face to face time with clients, and a corporate card with little oversight if we were being productive.

- Lots of opportunity to contribute back to platform teams and platform teams treating us like customers.

- Edit: also our clients themselves were interesting and doing cool things so that helped.