We investigate the Smalltalk-80 object-oriented programming environment as a tool for building graphical simulation models. We propose a simulation control framework for building discrete-event simulation models using Smalltalk-80. The main feature of the simulation control system developed is that it enables the user to develop his/her simulation models in a programming-free environment. The input of the simulation is based on the graphic layout of the model and the user's responses to a series of questions. We describe the underlying structure of the simulation control framework using a simple example.