A casting assistant plays an integral role in the acquisition of actors in both television and film. It's ultimately his job to find the most talented and appropriate actors for television and movie roles. While every job will differ slightly, the primary job duties of a casting assistant are basically the same. These include reading scripts and finding suitable actors to fill roles, contacting and negotiating with actors' agents, assisting in auditions and maintaining records on actors.
Usually the first responsibility of a casting assistant for each job is to read the script for a television series or film. During this time, he will go through each scene and get a feel for what type of actor each role needs. He will typically start off with a rough idea in mind, and gradually narrow it down until he has a list of the ideal actors. Once the casting assistant knows which actors are best suited for the production, he will usually discuss that information with the producers and director. During this time, he will make sure that everyone is in agreement and work out any other details concerning roles.
After the initial phases of this process have been completed, it's the responsibility of the casting assistant to contact the agents of the actors he has in mind. At this stage, he will check on the availability and interest of each actor for the production. He will also talk about contractual agreements and set up audition times for each actor.
During the auditioning period, it's the casting assistant's job to provide all actors with scripts and any other pertinent information for the role. From there, he will be part of the screen testing process and will typically run the camera for each audition. He will tape each actor's performance from a selected scene to be reviewed by the director and producers later on. It's also his responsibility to set up catering and to provide actors with beverages.
After all actors have auditioned, the casting assistant will then record any important information on each actor. Unless the actor is extremely well known, he will also keep a head shot and resume. Once he has this information, the casting assistant will send out the audition tapes along with any other relevant information to the director and producers. At that point, the bulk of the job is done, and the director and producer will finalize the rest of the casting process. After all actors have been given contracts, the casting assistant's job is complete and he will move on to his next assignment.