As an executive recruiter, your primary job duty will be to vet and choose the appropriate candidates for positions that your clients will bring to you. These will be high-level positions that are very important to the company, and they will trust you to be the first person to weed out anyone who is not fully qualified or passionate about the position.
In some cases, you may be charged with going out to proactively find people for open positions that your client companies have open. You may even have the leverage to make offers to people who are currently employed. In many cases, executive recruitment is a very competitive sport. You may be talking to people who are already in high demand or in the midst of contracts with other employers, and you may be charged with negotiating them out of that deal and into one with your client companies.
You may have a need for legal expertise as well. When you are making offers to clients who are already employed or in other contracts, you have to work around the legal hindrances that may be involved. Although your clients will likely have legal specialists on their teams, you are the first person to look at contracts and send out offers. If there is a problem with the legal portion of what you come up with in your negotiations, you will have to take responsibility for this mistake.