Hi. if you are into microcontrollers, some of them has built in TX/RCV for RS232. no need for level shifters. PIC 16f87xx series and some 18Fxxx are examples.
Only if you connect on logic level (ttl) you can leave out a level shifter IC. But then you should'nt call that RS232, because that implies using + and minus voltages.
So you can definitly not connect a 16F87 chip without a levelshifter (max232) to an RS232 device, cause the PIC is all ttl only.