For a shortened tailored jacket with a back seam (1.5 pieces), we recommend consulting this technical file where you will find precise instructions of the working method to follow and detailed sketches for a full and clear understanding. This new model can be made using the tailored jacket base pattern (3 pieces) as your starting point. For this example, the side piece is integrated in the front pattern piece, suppressing the seam that originally existed between these two pieces. With the suppression of this seam, the volume of the jacket is slightly fuller and less fitted on waist level. This tailored jacket is made up of one a half pieces, a front and back (without a center back seam). Using this new base as a starting point, other transformations can be brought. Adding a tailored sleeve or collar is possible, for example, and the following technical files will help you develop your model further: The technical file of the tailored sleeve base pattern The technical file of the puffed sleeve The technical file of the tailored collar The technical file of the shawl collar.