Brian Gross wrote: > you cannot have the same Source Element in two Source Element Groups... > It's really easy to get confused or to design yourself into a corner > if you're not careful (I know, I have). > I've found that using a spreadsheet that lists all my custom sources > and the source elements is essential to keeping track > of my custom elements. I second Brian's good advice. I also identify the source element groups which are used in each of my custom source types. For example see my Baptismal Register source type which lists by abbreviations (C, D, L, L2, PL, RA, Rp, RR, SbT, T, Vm) the eleven Groups used by that type: http://www.mjh-nm.net/SRCTMPLS.HTML#BaptismalRegister The Chapter of my book I referenced dealing with Source Elements http://www.mjh-nm.net/SRCELEMS.HTML organizes all the element groups and their variable name aliases according to "where" that element can be entered (Citation Screen, Repository Screen, plus Source Definition Attachments, Supplemental, and General Tabs). However, I have found a quick reference table of all the Source Element variable name aliases which exist helps to avoid Brian's valuable caution about duplicate names. See: http://www.mjh-nm.net/SRCELEMS_TABLE.HTML This table shows not only all the TMG default variable name aliases for each Source Element Group, but also includes my own custom names (beginning with an asterisk) which I use in my custom source types. This table is formatted to print out on one page which makes a handy reference when creating a new source type. The group name at the top of each column links to that group's entry in the main lists in the book. Hope this gives you ideas, Michael