It was, I suppose, inevitable that once the "marriage" between GPS and GIS technologies was consummated there would be an increasing demand for improvements in the quality of the products that supported them. Such is frequently the case in a marriage. Submeter accuracy has been the de facto standard for what has euphemistically been referred to as "mapping-" or "resource-" grade GPS receivers. But there have been rumblings of a cost-effective method of getting "survey-accurate" data into a GIS as well. GPS developers and manufacturers have been introducing a "new generation" of products designed to increase both accuracy and efficiency for users.