Hey, I use a lot of quartz calendars in my rules like this: rule "my rule" calendars "myCalendar" when But defining them in java is quite verbose. Also I often use the same calendar for only one rule. I believe the calendar is part of the logic and therefore don't like to initialize it elsewhere but with the logic code in the rule. DailyCalendar myCalendar = new DailyCalendar( 7, 0, 0, 0, 8, 0, 0, 0 ); myCalendar.setInvertTimeRange( true ); ksession.getCalendars().set( "myCalendar", QuartzHelper.quartzCalendarAdapter( myCalendar ) ); I would rather define calendars directly in the rule files or even exactly where I use them, e.g. rule "my super rule" calendars DailyCalendar( 7, 0, 0, 0, 8, 0, 0, 0, true ); when or defining them in the rule file like this: (example) declare "myCalendar" @role(calendar) @type( daily ) @from (7,0,0) @until (8, 0, 0) @invert(true) end and the use them as ever. I couldnt find anything like this in the documentation, but would not be surprised if it is actually already possible somehow. If not I would like to suggest this as a new feature ;) (I think I'd prefer the second example with declare) - Alex