Cook the orzo according to the package directions. Drain.
In a medium skillet, add the olive oil and red wine vinegar and saut the diced zucchini, diced yellow squash and halved tomatoes for 4 to 5 minutes, stirring occasionally.
Toss the cooked vegetables with the orzo.
Chill at least two hours in the refrigerator before serving.
Serve summer squash and tomato orzo Salad for a light lunch, or for dinner with a side of grilled chicken or fresh fruit.