The Space Telescope (ST) will require many types of standard sources for a diverse range of calibrations to be performed after launch. The scientific instruments are sensitive to a wide range of wavelengths from 1050 to 11,000Å and encompass a broad range of measurement capabilities including astrometry, photometry, imaging, polarimetry, and spectroscopy. To verify proper operations of each instrument and to provide quantitative calibrations, a diverse range of standard sources and fields are required. In order to select targets that satisfy the requirements of the Instrument Definition Teams and the long term responsibilities of the Science Institute, six groups containing a total of 25 astronomers are defining the calibration targets to be observed after launch. The six categories of ST standard sources are:

1. 1) Ultraviolet Spectrophotometric

2. 2) Ground Based Spectrophotometric and Photometric

3. 3) Wavelength

4. 4) Astrometric

5. 5) Polarimetric

6. 6) Spatially Flat Field

The data in these categories will be collected from the literature or through new observing programs as appropriate. These six reports of the working groups outline the calibrations and proposed targets for all of the scientific instruments on ST. The collected data on each set of standard sources should be published in the refereed literature.