Yes, There is no Edit method for ADO, but you can use Select statement and then trap the error code, the codes should be as follow:

On Error goto ErrorHandler
Dim mSQL as String
Dim rsMyRecord as ADODB.Recordset

mSQL = "Select * from MyTable Where MyCode = 'myCriteria' Order by MyCode"
rsMyRecord.Open mSQL,YourConnectionString ..., adOpenKeyset, adLockOptimistic
rsMyRecord.MoveLast

rsMyRecord!MyField1 = ...
rsMyRecord!MyField2 = ...
rsMyRecord.Update
rsMyRecord.Close

ErrorHandler:
Select Case Err.Number
case 0
Case 3021 ' Specified Record not found
' You May Add New Record Here
Resume next
Case else ' Trap another errors
...
...
End select

Best Regards
Winan