The Byzantine emperor established no permanent missions in foreign countries though he usually sent the same highly trusted nobles and clerics on his embassies. As a matter of practice, these ambassadors were familiar with the countries they visited, either through previous travels or through their ethnic backgrounds. Even so, they were thoroughly briefed before they set out. Not only were they drilled on the details of the goals to be achieved, but they were also apprised of current developments in the court they were visiting. Constant contact was maintained with Constantinople, and diplomatic missions could sometimes last up to a year. The Byzantines probably initiated the practice of sending regular diplomatic reports home to the government.