The obvious answer is it depends, but I will give you my opinion based on my experience. Most investors want to speak with the partners, so the fund needs to have real traction before it considers hiring a full time IR person. Assuming the fund is sub $250mm in AUM, I would hire a senior executive assistant or junior IR to help manage this role. Managing investors and scheduling is just as important, if not more important than interacting with the investors themselves. For example, if you are meeting 50 new potential investors over the next 3 months, that will take a considerable amount of planning, and believe me if you screw up a time or show up at the wrong place, you can pretty much kiss that opportunity goodbye. This role becomes essential when the partners can no longer physically answer the phone anymore because they are too busy. Use that as a guide.  The partners will be senior enough to hire a full time IR person that interacts (ie goes to meetings, etc) with investors when they no longer “need” new investors (usually greater than $100-150mm), but want more investors.