An implementation of the programming language Logo is described. Logo, a programming language somewhat like Lisp, is intended to teach the naive user the elements of programming and problem-solving, especially in symbolic programming applications such as graphics, natural language processing, musical composition, and the solution of elementary artificial intelligence problems. The system described here, BCLogo, is an attempt to build a portable implementation which would net be particularly sensitive to the computer on which it was run. The thesis describes both the manner in which the system appears to the user and the way in which the system was built. / Science, Faculty of / Computer Science, Department of / Graduate