No matter the size of your company, you must always be looking for new talent - even if you don't have available positions. Multiple times throughout my career I felt like we had a solid team and no one was looking to leave. In some cases I followed my own advice and had individuals "on deck". In many cases its easy to let the day to day grind get the better of you and forget this. Furthermore don't ever think that someone cant be replaced. I have lost some great employees over the years, only to find individuals that are much more talented.