It can be done but it does take two very special people. Jealousy is not an attractive trait to me. But I realize that not everyone is capable of dealing with this type of "career choice"
It's like swinging to me. I have been an active swinger for quite sometime and jealousy is no longer an issue for me. My personal opinion is that human beings weren't not meant to be monogomous creatures. We are animals and like the majority of animals in this world.. there are multiple partners.
But the girls that want to have an SO in this world must realize this is a two way street. You can't expect to do this type of "work" and your SO to have to remain monogomous to you.
I think that honesty is the biggest key to making this work. If you aren't honest about it and it is found out then the trust factor is gone. Be honest, let him decide if he can deal with it. And if he does agree, offer him a compromise. Set up a date for him with other providers every so often. It will even the playing field and make it all fair. But just like in swinging if both partners aren't willing then it will not work.