iTop

The best hub to build a single solution that covers various customers while protecting the confidentiality essential to every organization. Designed by very professional IT people to manage the complex shared infrastructure. Has the ability to analyze the impact of an incident or a change on various services and contracts that you have to fulfill.

It is always at the heart of operational activities for the service center strives to establish a single repository shared by all teams that allow you to define offerings that can fit each customer. Has satellites that have the capacity to synchronize central control with [the] remote customer to provide them with solutions linked with your operations.

We use it for IT issue tracking and ITSM

I think that it is very well suited for smaller companies who want a help desk stack with a monitoring integration like Zabbix for a completely open-source stack. I do not think that it is particularly well suited for large organizations where more robust helpdesks are available. ServiceNow may be a better option for a larger organization.