See http://www.opengeospatial.org/specs/?page=requests&request=rfpc28

The candidate OGC Web Processing Service interface specification provides a standardized interface that facilitates the access and publishing of geospatial processes as well as the discovery and binding to those processes by client applications.  "Processes" in this context include any sort of calculation or model which operates on spatially referenced data. Examples of geospatial processing are polygon overlay, buffer analysis, and line of sight analysis. The data required by the WPS can be delivered across a network or it can be available at the server. WPS builds on currently adopted OpenGIS(R) Specifications that define standard interfaces for finding and accessing geospatial data and services.

Comments can be submitted to a dedicated email reflector (see link
above) for a thirty-day period ending February 4, 2006. Comments received will be consolidated and reviewed by OGC members for incorporation into the document.

The OGC(R) is an international industry consortium of more than 300 companies, government agencies, research organizations, and universities participating in a consensus process to develop publicly available interface specifications. OpenGIS(R) Specifications support interoperable solutions that "geo-enable" the Web, wireless and location-based services, and mainstream IT. The specifications empower technology developers to make complex spatial information and services accessible and useful with all kinds of applications. Visit the OGC website at http://www.opengeospatial.org.