Ovaltine is a portable performance analysis tool that we have developed in the Centre for Novel Computing (CNC) over the past two years. It is used to analyse OpenMP codes, specifically those written in Fortran77. It instruments a copy of the source code, which is then executed to produce data. Ovaltine uses this data to determine various overheads for the given parallel implementation with respect to the given sequential implementation, displaying the results in a simple table. Instructions on using Ovaltine are given in a Word and Postscript version at doc/UsersGuide_versionX.Y.doc and doc/UsersGuide_versionX.Y.ps where X.Y is the release version. Ovaltine is copyright (C) 2000/2001 of The Victoria University Of Manchester, the Centre for Novel Computing and Michael Bane. Ovaltine is free software and is distributed in the hope that it will be useful, but without any warranty; without even the implied warranty of merchantability or fitness for a particular purpose. Ovaltine is not for commercial use. If you are unsure whether your purposes comply with these terms please contact ovaltine@cs.man.ac.uk