Some of the earliest  EHR systems were directed at the ambulatory care setting, as noted in discussions of developmental models in the EHR Overview/Background segment of this web site, and many of these  are in still in active use. Other systems now offered for the market have been derived from these developmental models while still others have arisen and been designed to be immediately marketed. There are still not even widely accepted consensus conceptual models for either the data to be contained or the core functions for using these data in these ambulatory EHR systems. The following Suppliers  for EHR systems, as reported in the eWeek website (http://www.eweek.com/article2/0,1759,1728486,00.asp), are currently active in the market: