[lmikle]

FindFirst/FindNext/FindClose;

Код:

procedure GetFolderList(APath : String; var AList : TStringList);
var
  iFound : Integer;
  F : TSearchRec;
begin
  AList.Clear;
  APath := IncludeTrailingPathDelimeter(APath);
  iFound := FindFirst(APath + '*.*',faAnyFile,F);
  While iFound = 0 Do
    Begin
      If (F.Attr And faDirectory) <> 0 Then AList.Add(F.NAme);
      iFound := FindNext(F);
    End;
  FindClose(F);
end;