This text has a three-fold purpose: (1) to teach assembly language in general and MACRO-11 in particular, (2) to teach the computer architecture of the PDP-11, the LSI-11, and the Professional 300 series of computers, and (3) to demonstrate how the concepts of structured programming can be applied to assembly language. The examples used to illustrate the various concepts are complete in the sense that they proceed from the verbalized problem through the logic design and coding stages to the final output. The student sees the entire developmental process through which the programmer proceeds to produce the final program.