Current computer programs for intracellular recordings often lack advanced data management, are usually incompatible with other applications and are also difficult to adapt to new experiments. We have addressed these shortcomings in e-Phys, a suite of electrophysiology applications for intracellular recordings. The programs in e-Phys use Component Object Model (COM) technologies available in the Microsoft Windows operating system to provide enhanced data storage, increased interoperability between e-Phys and other COM-aware applications, and easy customization of data acquisition and analysis thanks to a script-based integrated programming environment. Data files are extensible, hierarchically organized and integrated in the Windows shell by using the Structured Storage technology. Data transfers to and from other programs are facilitated by implementing the ActiveX Automation standard and distributed COM (DCOM). ActiveX Scripting allows experimenters to write their own event-driven acquisition and analysis programs in the VBScript language from within e-Phys. Scripts can reuse components available from other programs on other machines to create distributed meta-applications. This paper describes the main features of e-Phys and how this package was used to determine the effect of the atypical antipsychotic drug clozapine on synaptic transmission at the neuromuscular junction. (C) 2003 Elsevier B.V. All rights reserved.