Donīt date within your own department

While dating within the same company is iffy at best, dating within the same department is almost never a good idea. Departments need to work together in an unbiased manner, setting priorities and making decisions. If two people within a department date, then every decision they make - which task to work on first, how much time to spend working on X - will be second-guessed by the rest of the department, and indeed the company.