Drain pineapple and reserve the juice.

Dissolve gelatin in pineapple juice and enough hot water to make 2 cups. Boil.

Add fresh or frozen strawberries and pineapple. Remove from the heat.

Lightly grease a 9" x 12" pan. Pour 1/2 of the mixture in the pan and refrigerate until just beginning to set. Spread 1 pint of yogurt over this, then spoon the remaining mixture over the top of the yogurt. Refrigerate until firm.