These controls need to be counter-balanced, however, with the need to respond to external systems that need to clear their transactions. For example, complex sales channels may have a need to create a "new" account that in fact already exists in your CRM system. The external system may show the account with a different name (formal legal entity versus "street name"), a different city, or other key information that is different from what you already have.

The same issue applies to an Opportunity that you might (or might not) already have in the system. At the time that the transaction comes in, there may be no way to know which version of the data is better--and sometimes both versions might need to be maintained for later reconciliation.

So our recommendation is that you purposefully create a duplicate record, with pointers to the record you believe is already there. When the record is created, an alert should be sent to your sales operations or accounting department for subsequent evaluation and data reconciliation. Typically, the new record will be made a child of your existing record in a master-detail relationship, so that the outside system can continue to update the "copy" of the data that it likes&and your accounting system can get the roll-up data it needs to balance the books.

This is a fairly straightforward decision when the Account name is nearly identical. It's a bit more of a judgment call when the new Account is ESPN and the existing Account is ABC Networks or even Disney. They're all part of the same corporation, but do they need to be a single account, or an account hierarchy? It all depends on your business rules.

OK, but what about other CRM tables? It's not at all unusual to have noisy data updates coming in for both Leads and Contacts. The data are noisy in three key ways: