In a mixing bowl, combine the graham cracker crumbs and sugar. Add the melted butter, and stir until the crumbs are well moistened.
Press the mixture into a 9-inch pie dish, forming an even layer on the bottom and up the sides. Bake at 350°F for 10 minutes, then allow to cool.
Whisk together the sweetened condensed milk, lemon juice, and egg yolks until smooth.