The PEST Suite

Browse these pages to:

  • learn about PEST and its utility support software;
  • download this software;
  • understand the importance of uncertainty analysis and data assimilation in decision-support modelling;
  • access educational resources;
  • purchase the PEST book.

PEST – the Book

The PEST book collects in one place all of the theory on which PEST and its suite of utility software is based. It also discusses important issues like how models should be used in the decision-making context, uncertainty analysis, model-based hypothesis testing, and the effects of model defects on calibration, prediction and uncertainty analysis. This book makes an essential reference text for those engaged in environmental modelling. is a PEST cloud enabler developed by S. S. Papadopulos and Associates. It gives a modeller ridiculously easy access to the cloud computing environment when model calibration is undertaken using PEST_HP, a version of PEST that is optimized for use in parallel computing environments. A user does not need to know anything but the barest essentials about cloud computing. Uploading/downloading of PEST and model files, distribution of files to computing nodes, and shutting down of those nodes when the inversion process is complete, is all taken care of.


The PEST++ suite provides model-independent decision-support functionality that complements and extends that provided by PEST. It is compatible with PEST, both in its file structures and its philosophy. Hence it can be used interchangeable with PEST. Visit the PEST++ GitHub site to find out more.


GMDSI stands for "Groundwater Modelling Decision Support Initiative". This project is currently being carried out under the auspice of the National Centre for Groundwater Research and Training, Flinders University, Australia. Its sponsors are BHP and Rio Tinto.

GMDSI’s mission is to promote, facilitate and support the improved use of models in groundwater management, regulation and decision-making. It pursues this mission in the following ways:

  • Promulgating increased industry proficiency in decision-support modelling through education and training;
  • Promoting industry-wide discussions leading to improved perspectives on the role of modelling in groundwater protection and management;
  • Promoting and facilitating the use of model-value-adding software such as PEST and PEST++.

See the GMDSI web pages to find out more.

John Doherty, the author of PEST, is helping to manage the GMDSI project. As data assimilation and uncertainty quantification software such as PEST is integral to decision-support modelling, his involvement in the GMDSI project overlaps with his work with PEST, and in teaching people how to use PEST. Through John's involvement in this project, GMDSI is contributing to maintenance and enhancement of the PEST suite, and to the development of training resources for decision-support modelling. Some of these resources are featured in these web pages.


The help provided by S.S. Papadopulos and Associates and ESI (in particular, Jim Rumbaugh) in hosting these pages, and in supporting development and maintenance of PEST generally, is gratefully acknowledged.