In order to determine the knowledge and skills needed by novice programmers to successfully learn computer programming, four studies were conducted using a clinical interview technique. The first study determined that many systematic errors in programming were due to programmers' high-level misconceptions of the nature of the computer and of the syntax and semantics of the programming language. The second study found that many misconceptions could be remediated effectively through a combination of (1) explicit training about the syntax and semantics of specific constructions in the programming language, (2) requiring learners to predict outcomes of short programs, and (3) providing students with interactive computer feedback. The third study examined methods used by high school teachers in computer programming instruction, and the fourth considered students' use of their existing knowledge. Findings indicate that, when Pascal programming functions are embedded with other functions, the embedded functions are evaluated incorrectly by novice programmers more often than when they are evaluated in their unembedded form. Results suggest a lack of a standard curriculum at the high school level and weaknesses in high school courses and textbooks in their treatment of debugging. Four references are listed. (LMM)