BETWEEN dates in dynamic sql

I get the following error when I run the following stored procedure: 'ODBC Error Code = 22008 (Datetime field overflow)
[Microsoft][ODBC SQL Server Driver][SQL Server]Syntax error converting datetime from character string.'  It will be a miracle if I get this working, it is driving me crazy.  Thanks in anticipation of any help.

SET QUOTED_IDENTIFIER ON
GO
SET ANSI_NULLS ON
GO

CREATE PROCEDURE sp_GetDaybook
@sContactIDList varchar (1000),
@sStock varchar (20),
@dtFrom datetime,
@dtTo datetime

AS

DECLARE @MySQL varchar (500)
DECLARE @MyWhere varchar (1200)
DECLARE @MyOrder varchar (100)

SET @MySQL = '
SELECT sDaybookID, sClientID, iContactID, dtComment, sStock, sAuthor, sComment
FROM   Daybook'

SET @MyWhere = '
WHERE 0 = 0'

IF @sContactIDList IS NOT NULL SET @MyWhere = @MyWhere + 'AND iContactID IN' + '(' + @sContactIDList + ')'
IF @sStock IS NOT NULL SET @MyWhere = @MyWhere + 'AND sStock LIKE' + '''' + '%' + @sStock + '%' + ''''
SET @MyWhere = @MyWhere + 'AND dtComment BETWEEN' + @dtFrom + 'AND'+ @dtTo

SET @MyOrder = '
ORDER BY dtComment Asc'

EXEC (@MySQL + @MyWhere + @MyOrder)

GO
SET QUOTED_IDENTIFIER OFF
GO
SET ANSI_NULLS ON
GO