Melissa Gilbert

Casting has begun for one of the most thankless roles in Hollywood: president of the Screen Actors Guild. Tired of infighting and what she called an "untenable" situation, actress Melissa Gilbert said Thursday that she wouldn't seek a third term as SAG president. Her departure sets the stage for what history suggests could be another contentious battle for control of Hollywood's biggest and, many say, most dysfunctional union.

Actress Melissa Gilbert plans to run for reelection in November as president of the Screen Actors Guild, joined by actor James Cromwell as a candidate for secretary-treasurer. Wednesday's announcement came after a Gilbert-backed plan to fold SAG into a new super union along with the American Federation of Television and Radio Artists narrowly failed, despite receiving 58% approval from SAG members. The plan needed 60% to pass.

Actress Melissa Gilbert on Tuesday won a starring role as president of the Screen Actors Guild for the second time, a victory for a less strident wing of the 118,000-member union. The election comes as SAG is on the verge of forging a new three-year contract with advertisers that could be announced as early as today. SAG and advertisers started formal negotiations only Tuesday, although union and company representatives have been crafting a deal behind the scenes the last few weeks.