A Service Catalog enables you to display the services offered to your end-users. Some of the most common day-to-day IT services required by users are, installation, relocation, provision of internet access and email access, virus protection, provision of hardware and software, mail server and account management.
The Service Catalog improves the operational efficiency of your support team by managing the service delivery process from approval to fulfill. You can also define the time involved for delivery of each service item and bind it with a Service Level Agreement. Service Catalog enables you to create, maintain, assign approvers, define processes, deploy and monitor all your services.
In ServiceDesk Plus MSP, the term 'Request' is used to refer both the Incident and Service Request collectively.In ServiceDesk Plus MSP, the term 'Request' is used to refer both the Incident and Service Request collectively.
An Incident denotes an unplanned interruption to an IT Service or a reduction in the Quality of an IT Service which might affect the user, a group of users or the business itself.
Examples: The system response time is slow, Unable to login to CRM tool, the payroll server is down.
Service Requests are requests raised by the user for information or advice, or for Standard Change or access to an IT service.
Examples: Need a new laptop, Require a user manual, Need access to a report, Reset a password.
You can manage the Service Categories under Admin -> Service Catalog -> Manage -> Service Categories. You can add, edit or delete a Service Category from this page. You can also set an icon for the Service Category from the list of available icons or you can upload a new icon for the same.
In Service Catalog, you can create two types of additional fields.
Common Additional fields are custom fields which can be created and used on every service template across all Service Categories. You can add 24 Text fields, 8 Date/Time fields and 8 Numeric fields.
Service Category specific additional fields are custom fields which can be created and used on services under a specific Service Category. The additional fields under every Service Category has 24 Text fields, 8 Date/Time fields and 8 Numeric fields.
The two ways of creating Additional fields are,
1.) Goto Admin->Service Catalog->Manage->Additional Fields and create the additional fields and then later add them under the respective service template. 
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b.) You can add the additional field from each service template under Admin->Service Catalog. While you are on the template, drag the 'Add New Field' option onto the canvas which gives you the option to add the additional field. 
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Resource Info is a functionality which is similar to Additional Fields but provides more options to collect the necessary details about the requested service from the user. You can collect the information by framing simple yes or no questions, questions with drop down selection, check boxes and plain text boxes. The drop down selection has the ability to sync with the Asset Management module to provide asset information on the drop down list. The questions can also be divided into different sections for a more organized view.
You can configure approvers for a service template under the Work Flow tab. The approver can be a requester or a technician with the permission to approve service requests. A user who is not registered in the application cannot be made as a service request approver.
The $Dept_Head$ variable is a dynamic pointer indicating the Head of the Department of the user who is raising a service request. The Department Head has to be pre-configured for every department under Admin->Departments before you could use this variable. Once the Department Heads are configured, and the variable selected in the service template, the approvals for that service is automatically sent to the user‘s Department Head when the service request is raised. 
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Yes, it is possible to turn off the 'Technician Auto Assign' feature for Service Requests alone but this has to be configured through the database by executing the query below (works for both MYSQL and MSSQL):
update globalconfig set paramvalue='true' where parameter='enable_tech_auto_assign';
You can restrict users from accessing certain services by creating User Groups in the Admin module. The User Groups are account-based and can be created for Users/Requesters based on different criteria such as Sites, Department, Job Title, or you can even pick users individually for the group using the criteria Requester Name.
Once you have configured the User Groups, you need to select the Show to Requester option under the Form Designer tab of the service template; then select the user groups to which you want to show this service.
The SLAs defined under Admin--> Service Level Agreements are applicable only for Incidents and not to Service Requests.
In Service Catalog, a static SLA has to be assigned to every service template under the Work Flow tab for each account. 
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The SLAs can also be managed from the Admin->Service Catalog->Manage->Service Level Agreements. Screenshot
You can link two or more Service Requests using the 'Link Requests' feature. Once the Service Requests are linked, the Notes, Worklogs and Resolution can be copied to all the linked requests from the parent request. It is also possible to link between Service Requests and Incidents. But as of now, ServiceDesk Plus does not support merging of two Service Requests. 
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Service Requests cannot be created through e-mail. You have to login to the Self-Service Portal, browse through the services and submit your service request.
It is possible to create a Change from a Service Request but it's not possible to create a Problem from a Service Request or associate a Problem to a Service Request.
Goto Admin -> Service Category and select a service under a Service Category. In the service form, select the accounts to associate this service. The selected accounts would be able to view the service template. 
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Goto Admin -> Service Catalog and select a service under a Service Category. Select an Account under the Work Log tab and select an SLA for the service template. Click Copy to Account(s) link to copy the selected SLA to other accounts. 
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This can also be done from the Admin->Service Catalog->Manage->Add SLA/Choose the SLA from the check box->Actions and click on Copy To Accounts as shown below. 
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