McNamara, 34, had been without a club since he was released from Aberdeen in April and Falkirk boss John Hughes could not his delight at the signing.
"Jackie is different class. The ultimate profession, who can play in a number of positions," beamed Hughes.
"It will also help raise the club's profile to sign a player of Jackie's stature and reputation.
"Jackie has bags of experience at international level and importantly experience in big games and of winning things, something we will need at Falkirk if we are to kick on take the club to the next level.
McNamara is hoping to making an impression on Hughes, having already played with his new manager at Celtic.
"He (John Hughes) is w ell respected in the game and I am looking forward to working with him again. The facilities here at Stirling University are first class and I a very impressed by the set-up."