Well that depends. If you are going to communicate with QuickBooks through linked tables, then it will be slow. If you construct queries that grab all the data from a table, then it will also be slow. However, a well formed query goes a long way, only grabbing what you need is key. You should only use linked tables when you want to send a SQL command to do an UPDATE or INSERT, otherwise your best bet is to do pass-through queries and copy whatever tables you need to your local database for SELECT statements. Do whatever reporting you need from the local tables to avoid the comm delays. Additionally, I recommend running the QODBC optimization process so that the B-Tree is formed in SQL. This indexing and sorting is paramount for efficient retrieval of data. That alone would speed it up dramatically.