Nico,
use a TIB_MonitorDialog to find out exactly what is taking so long. It
doesn't sound like a problem with your query since it is fast
interactively. But, does it help if you change to using subselects (a shot
in the dark, your MonitorDialog will help infinitely in making a proper
diagnosis)?

SELECT DealerNo, Name, Contact, Alfa, Title, Address1, Address2, Zip, City,
Phone, Fax, E_Mail, Website, Comment, Vat, Country_EG, Reduction,
BankAccount, Foreign_BankCode, Foreign_BankName, Foreign_BankCity,
Foreign_BankSwift, General_Acc, Coin,
(SELECT B.Name FROM Country B WHERE B.Code = A.Country),
(SELECT C.Province FROM State_Prov C WHERE C.Code = A.State_Prov),
(SELECT D.DescrCoin FROM D WHERE D.Code = A.Coin),
(SELECT E.Descr_1 FROM Deliv_Cond E WHERE E.Code = A.Deliv_Cond),
(SELECT F.Descr_1 FROM Payment_Cond F WHERE F.Code = A.Payment_Cond),
(SELECT G.Language_Descr FROM Language G WHERE G.Language = A.Language)
FROM Dealer A
WHERE DealerNo = :qDealerNo

Is it still as slow? Does your program use events?

Set