While professional lighting and sound can improve the quality of any event, for some activities, they're absolutely essential. Live music, plays, comedians, magic acts, and other performers require top-notch lighting and sound, to properly showcase their talents. In fact, most contracts will specify that certain equipment be provided. If the site itself doesn't have acceptable lighting and sound, you'll have to rent it. This can be expensive, so be sure to include these rentals, when figuring your entertainment costs. You'll also need an experienced crew to set-up and take down all the equipment. Because such matters are highly technical, it's imperative to let a professional handle the details. He or she can advise on what type of sound system you might need, as well as other gear like track lighting, floods, colored spotlights, and microphones. There's nothing more irritating than attending a guest lecture, and having to strain to hear the speaker; equally upsetting is a band that's so overly amplified, you can feel the bass in your stomach. In addition to enhancing a speaker or performer, lighting can serve many other purposes: for example, encouraging conversation at tables, or accenting artwork and displays.