Rinse couscous under cold water until water runs clear.
In a saucepan over medium heat, bring the broth to a boil. Add couscous and cook according to the directions on the package.
In the meantime, heat the oil in a saute pan on medium heat. Saute the yellow squash until it starts to soften, approximately 3 - 5 minutes. Add in the olives, sundried tomatoes, and lemon juice; cook for another 3 - 4 minutes. Toss in the couscous. Season with salt and pepper to taste before serving.