The ancient Persians are regarded by many historians as one of the greatest ancient empires in the history of the near east. Their strong army and leadership lead to massive land holdings. Because of this, they had to enact a number of policies and ideas to organize and control their large empire. 

Firstly, the Persians developed a new system of government that was more effective for ruling large groups of people. The Persians divided up their land holdings into "20 provinces", known as satrapies. Each of these satrapies was ruled by a governor, similar to the way states in the United States are governed today. These governors were known as satraps. The King would then send government officials to check on each region and make sure that they were conforming to the King's beliefs and wishes. 

Secondly, they became the first empire to govern conquered people by allowing them to have equal rights and responsibility as the citizens of Persia. The King would not interfere with traditions or customs of the conquered peoples, so long as they paid taxes and maintained peace. This differed from many of the Persians contemporaries who would often enslave captured peoples. 

Thirdly, the Persians developed an efficient communication system, so that news, orders, and information could be carried quickly through out their large empire. This was accomplished through the construction of a "royal road" that ran over 1,600 miles long, with various places along the way for messengers to stop and resupply or change horses. This road ran between Sardis and Susa, and allowed the King's messengers to cover the whole empire in as little as one week.

Hope this helps!