Overview
A monitor only matters if the right people see the alert. Notification groups are the roster mechanism: a named group contains a list of email addresses, and you assign a group to each monitor. When the monitor alarms, everyone in its group gets the email. This beats editing each monitor individually every time an on-call person joins or leaves.
Groups also let you separate routing concerns. An analytics team cares about GA4 sessions; a marketing lead cares about paid conversion drops; an on-call rotation cares about everything at 3am. Each audience gets its own group, and each monitor gets assigned to the group whose people actually own that metric.
Navigate to Notification Groups
Open Observer > Notification Groups from the left sidebar. The page lists every group on your property, along with the number of recipients and the monitors assigned to each. Click Add Group to create a new one.
Name the group
Give the group a clear, descriptive name: Analytics Team, On-Call, Marketing Leads, Client X Stakeholders. This name shows up in the monitor edit form's dropdown, so a future you (or a coworker) can pick the right group without having to inspect each one's recipient list.
Avoid naming groups after individuals ("Sarah's alerts"). People rotate, leave, and change roles, and group names that referenced them become stale. Use role-based names so the routing intent survives personnel changes.
Add recipients
Add email addresses for everyone who should receive alerts from this group. There's no cap; add as many as you need. For team-wide groups, consider using a shared distribution list address so adding and removing team members happens in your identity provider rather than in Observer.
When an alarm fires, every recipient in the group receives the same email, which includes the metric value, the threshold that was breached, and a link back to the monitor detail page. They don't see each other's addresses; each email is sent individually.
Assign to monitors
Open any monitor (or the new monitor form) and pick the group from the Notification Group dropdown. Save the monitor. From that moment on, alarms on that monitor flow to everyone in the group.
Each monitor is assigned to exactly one group. If a monitor should notify multiple audiences, add all the relevant people to a single group rather than trying to multi-assign.
Create multiple groups for different teams or escalation levels so routine analytics alerts don't wake up the on-call rotation. Each monitor can be assigned to exactly one notification group, so think in terms of "who owns this metric" when you build the group list. Email alerts include the metric value, threshold, and a link to the monitor so responders can investigate without clicking through multiple screens.
Troubleshooting
Alert fired but no email arrived
Check the recipient's spam folder first; transactional alert emails occasionally get flagged. If nothing is there, confirm the email address on the group is correct (typos are more common than you'd think) and that the monitor is actually assigned to the right group. The monitor detail page's run history shows which group was notified on each alarm.
Some recipients get alerts, others don't
Almost always a mail-server filter on the receiving side. Ask the affected recipient to check their spam folder and to whitelist the sender domain. If they use a strict corporate mail gateway, you may need to coordinate with their IT team to allow the sender.
Too many alerts arriving for the same incident
Observer deduplicates each alarm for 25 hours, so you shouldn't see the same monitor alarming repeatedly within that window. If a team is getting spammed, the cause is usually multiple monitors all tripping on the same upstream issue. Consolidate overlapping monitors so a single incident generates a single alert rather than five.