In a large bowl, cream butter and sugar until light and fluffy. Beat in the lemon juice, zest and extract.
Combine the flour, rosemary and salt, then gradually add to the creamed sugar mixture. Mix well.
Shape dough into two, 12 inch rolls. Wrap each one in parchment paper and then plastic wrap. Freeze 30 minutes or until firm. Unwrap and cut into 1/4 inch slices.
Place 2 in. apart on a parchment lined cookie sheet. Bake for 8 – 10 minutes. Cool for two minutes before removing to a wire rack. Store in airtight containers.