How do you get your work solicited?

Agents, publishers, theatres, TV companies etc read something of yours and decide it's not right for them but they like your work, so ask you to send something else in- maybe even suggest a theme/idea. Then what you send in becomes solicited ie. not entirely cold-calling like most stuff that lands on their desk. Or they might see a play of yours in a little pub theatre, or read a story in a small magazine, or you might be lucky enough to know someone, who knows someone, who suggests you send them something... It's all about getting the first foot in the door really.