I'm creating some models to assist other staff in a big geoprocessing project coming up, both to streamline their workflow and provide a level of data integrity protection. One of the functions I want to emulate in Model Builder is to calculate a field on ONLY selected features. The MakeFeatureLayer_management tool will work most of the time, but if the user hasn't selected any features on the layer before using the tool, it seems that the tool will then calculate the field for ALL records. I want to make it so that if no features are selected, nothing happens. Any suggestions would be appreciated. Thanks.