jClamp for Windowsis a user-friendly whole-cell voltage clamp data acquisition program which features real time monitoring of cell and voltage clamp characteristics. The program has no frustrating menu labyrinth. Instead all choices are displayed on each main window or, in some cases, mouse movements over an area on the window pops up additional choices. At all times the patch clamper can determine cell status. Data collection is initiated through a rapid parameter directory (RPD) which maintains a list of 18 parameter filenames or script filenames. Either a key press or mouse click begins the predefined voltage or current delivery protocols. Scripts are text files that allow groups of parameter files to be called and run. Most tasks are automated. Some data analysis is available. However, data is saved in axon binary format (.abf), and can be loaded into programs like Clampfit and Axoscope (Axon Instruments, CA). Additionally, data can be exported in ASCII format or via automation to MATLAB Origin, Sigmaplot, and Excel for further analysis. When the mouse icon is placed over a particular item in a jClamp window, be sure to check for quick information on that item in the left, lower panel of the main jClamp window.