---
title: "Understanding the relationship between system events, subscriptions and notifications"
slug: "understanding-the-relationship-between-events-subscriptions-and-notifications"
tags: ["notification service ", "architecture"]
updated: 2024-09-23T15:06:06Z
published: 2024-09-23T15:06:06Z
canonical: "support.lusid.com/understanding-the-relationship-between-events-subscriptions-and-notifications"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://support.lusid.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Understanding the relationship between system events, subscriptions and notifications

LUSID and other applications in the LUSID ecosystem, such as Drive, Scheduler and Luminesce, emit *system events*. Each system event has a set of *attributes* that describe that event. [See the list of events and their attributes](/v1/docs/what-system-events-can-i-subscribe-to).

You can create as many *subscriptions* as you like to a particular system event. You can [subscribe](/v1/docs/how-do-i-subscribe-to-an-event) every time the event occurs, or filter on event attributes to subscribe only in a particular set of circumstances.

You can create as many *notifications* as you like and attach them to a subscription. A notification can trigger people via email or SMS, or a service via Amazon SQS or a webhook. This service can be LUSID itself, or a third party API.

Consider the following example of a system event with two subscriptions, each triggering a set of notifications in different circumstances:

![](https://cdn.document360.io/d575ad81-c0ed-4980-bbd1-d59ac5c3de82/Images/Documentation/0237e297-2dfe-480f-bf4c-112f73c174b9.png?sv=2026-02-06&spr=https&st=2026-11-04T02%3A00%3A42Z&se=2026-11-04T03%3A00%3A42Z&sr=c&sp=r&sig=gP1ZgcRlYU1tlcqF%2FK2J0luISErauZUmpD6zKo80y7A%3D)