Context is everything, and you've given none. However, one might guess that as you've used initial uppercase for both words they might form a business name. If so, then Tomorrow's Lighting might well be correct, assuming the business sells futuristic lighting: the lighting of tomorrow.
"STYLE is knowing who you are, what you want to say, and not giving a damn." — Gore Vidal "STYLE is knowing what sort of play you're in." — Sir John Gielgud