The Interactive Graphics Utility for Automated NEC Analysis IGUANA is a computer program designed to reduce the time for antenna model evaluation by providing partial automation to both the data entry process and the data display process. IGUANA is an aid to NEC input data preparation and NEC output data display IGUANA performs no antenna evaluations itself. IGUANA resides on a microcomputer an IBM XT or compatible and is independent of the main frame on which NEC resides. IGUANA is a composite of independently developed but fully integrated subprograms designed to aid in preparation and display of NEC related data sets. The effort required for NEC model composition and data entry is significantly reduced by the use of IGUANA hence the time required to prepare an error free data set constituting a valid NEC model may be significantly reduced from weeks to a matter of hours in some cases involving very complex models.