>>>>The following is very slow, presumably because of my use of IN

Select * From KTrackTagDetail							;
>>>>	where (Seqno In (Select Seqno From C_Kits)			;
>>>>	or SeqnoFG In (Select Seqno From C_Kits))			;
>>>>	and Left (RecordType,2) # 'AP'						;
>>>>	into Cursor C_Detail

>>>>So, how can I speed this up?
>>>>
>>>>Thanks
>>>
>>>
>>>Try ONE left join insstead of two select queries
>>>
>>>

>>>Select * From KTrackTagDetail ;
>>>	left join C_Kits on (  KTrackTagDetail.Seqno ==  C_Kits.Seqno ) ;
>>>		or    (  KTrackTagDetail.SeqnoFG ==  C_Kits.Seqno ) ;
>>>	where (  Left (RecordType,2) # 'AP' ) ;
>>>	    and ( C_Kits.Seqno is not null )
>>>

>>
>>LEFT JOIN is not the same as IN condition. This is not equavalent to the original query.
>
>Who cares - it'll probably run faster - with the same results

See answer from Boris - it will not return the same number of records if you have One to Many relationship between these two tables.