David is Head of London Employment, which is tier 1 ranked in Legal 500 UK and has been shortlisted for IEL's disputes team of the year and investigations team of the year.

David advises global firms in the financial services and technology sectors on: 

• complex discrimination, whistleblowing and breach of contract litigation 
• privileged and open investigations 
• employment regulatory issues facing regulated firms 
• board level issues
• confidentiality and restrictive covenant disputes 
• strategic international projects 
• employment aspects of corporate transactions 

He is a member of the City of London Law Society's Employment Law Committee.

Endorsements:

According to Chambers and Partners UK (2025), "David Sims stands out for his high-quality representation of clients in the financial services market [and] has experience advising on sensitive investigation matters".

Clients comment, "He’s approachable, easy to talk to and brings a collaborative style that makes even complex issues easier to navigate", "He is commercially very astute, very hands-on and ensures the job is done", and "David is an excellent commercial lawyer who takes the time to understand our business and feels like an extension of our team. He is extremely responsive, thorough and a pleasure to work with." (Chambers and Partners UK, 2025)