The MCC building had three wings: on the left side the Operations Wing, on the right side the Mission Support Wing (or Administration Wing) and a Lobby Wing in the center. The Operations Wing had two Mission Operations Control Rooms (MOCRs) on the second and third floor respectively. The elaborate systems for mission support: the Real Time Computer Complex (RTCC) and the Communication, Command And Telemetry Center (CCATS); were located on the first floor.

MOCR-1 has been mainly used for training and simulation.
However the following missions have been controlled from MOCR-1: Apollo 5, Apollo 7, the Skylab missions and the Apollo-Soyuz Test Project.

MOCR-2 was used as the primary room for flight control and mission management.
It has been used for the Gemini missions 4 to 12 and all the Apollo missions in which the Saturn V was used as the launch vehicle.
(The Gemini missions 1,2 and 3 were controlled from the Mercury Control Center at Cape Canaveral Missile Test Annex, Florida.)

On the same floor the Recovery Control Room (RCR) was located. This room arrangement bears some resemblance to MOCR. The crew of the RCR was in command in the last phase of the mission when the command module was reentring Earth's atmosphere and was on its way to its calculated landing area somewhere in the Pacific Ocean. There was a window between MOCR-2 and the RCR, it enabled the DOD officer, sitting at the top row in MOCR-2, to keep an eye on the activities in the RCR. DOD was responsible for the recovery activities.

The Communication, Command and Telemetry System (CCATS) was the heart of a communication system between the spacecraft and the flight controllers. CCATS was connected to an elaborate world-wide network of tracking stations, stations to maintain data and voice communication with the spacecraft and communication relay satellites. CCATS had three UNIVAC 494 mainframe computers for data processing one as the Mission Operational Computer (MOC), a second as a Dynamic Standby (DSC) and a third UNIVAC 494 as a reserve available for other tasks.

The Real Time Computer Complex (RTCC) was used to transform data from CCATS into data suitable to display on the various console screens used by the flight controllers. The RTCC was also used to calculate and plot flight trajectories and to prepare data and commands to be uploaded to the spacecraft's on-board computer via CCATS. With five IBM 360 mainframes the RTCC had more computer redundancy than CCATS with its three UNIVACs 494.

In this diagram is shown how CCATS and RTCC could be configured in such a way that both centers can support an ongoing mission and support the training of flight controllers for the next mission at the same time. There were two Mission Operations Control Rooms (MOCRs) available to enable mission support and training simultaneously.

A system named ASCATS (Apollo Simulation Checkout And Training System) was used to simulate an Apollo mission. ASCATS was not part of the Mission Control Center, it was residing in another building at the Johnson Space Center.
The data generated by ASCATS to simulate data from launch vehicle, spacecraft and remote sites were indistinguishable from real mission data. With ASCATS data could be generated to simulate all kinds of malfunctions to train the crew, prepare them for various eventualities and to validate procedures. ASCATS could be configured in various ways for training the crew of the Mission Control Center, for training the astronauts and for training the crew at various remote sited. In a so called integrated simulation all groups were involved.