Notification checks & escalation

Hi, I have a problem with the configuration of nagios: i have more than 80 hosts and 160 services checks.
All works right but sometimes i got strange behaviors.

What i want is this: when a service check fails, before sending out the notification nagios should check the host, then:
a) if the the host is down, send out the notification only for the down of the host;
b) if the host is up, send out the notification of the service fail.

How can i do this?

Thank you

this should be the standard behaviour if i’m not mistaken.
Check you don’t get notified for unkwnon statuses.

Luca