Soldiers in the Continental Army were volunteers; they agreed to serve in the army and standard enlistment periods lasted from one to three years. Early in the war the enlistment periods were short, as the Continental Congress feared the possibility of the Continental Army evolving into a permanent army. The army never numbered more than 17,000 men. Turnover proved a constant problem, particularly in the winter of 1776–77, and longer enlistments were approved.