When importing data from an external source system to update a constituent record in CRM, it is possible to use an alternative lookup ID to find and match to an existing constituent record. However, it is not possible to add a alternative lookup ID type to constrain which set of alternative lookup IDs CRM is trying to match to. This creates a problem for customers who have multiple alternate lookup ID types from different systems with overlapping ID ranges. For example: constituent A in CRM has an alternate lookup ID - 123456 of type "Data warehouse" and an alternate lookup ID - 654321 of type "Finance system"; constituent B has an alternate lookup ID - 111234 of type "Data warehouse" and an alternate lookup ID - 123456 of type "Finance system" If the customer creates a Constituent Update batch to load data from their Finance system and includes constituent B's record and uses the finance lookup ID - 123456 in the import file, in CRM either constituent A or B could be a match, as there is no validation of alternate lookup ID type. There is a danger the wrong record could be updated. Possible solutions - When an alternate lookup ID is used in an Import file to find and match to an existing constituent record, the alternate lookup ID type should be included in the file and the matching routine should be constrained to look for matches only within that type.