Abstract The objective of this two part paper is to present a method of enhancing accuracy of fabric drape simulation using commercially available software. In Part I, we report results of an investigation of drape variability for a set of fabrics having varied mechanical properties, an essential step in defining accuracy for drape simulation. Results illustrate that fabric drape behaviour is highly variable and thus provide no single drape configuration to target with simulation. Development of a revolutionary method for capturing drape of actual fabrics and measuring that drape in a virtual three-dimensional (3D) environment is also presented. The method allows identical drape measurement processes to be implemented for actual and simulated fabrics and provides opportunity for use of additional measures to assess fabric drape in three dimensions. The accomplishments presented in this paper are utilized to demonstrate, in Part II, development of a relationship that enhances realism of particle model simulations generated using the commercial drape simulation software.