Related Lists and Related List Configuration

Why Related Lists Matter
Related lists are one of the most visible and heavily used parts of every Salesforce record page. When a sales rep opens an Account, the Contacts, Opportunities, Cases and Activities they see beneath the details are all related lists. For the Advanced Administrator exam, this topic sits inside the Advanced Objects and Applications domain, and it is tested because related lists connect several core skills at once: the data model (lookup and master-detail relationships), page layouts, Lightning App Builder, security (object permissions, field-level security and sharing), and user experience design. Questions rarely ask you to define a related list; instead they describe a business scenario and expect you to pick the right configuration tool that produces the required result with the least effort and without custom code. Understanding exactly what each tool can and cannot do is the key to scoring well.

What a Related List Is
A related list is a component on a record page that displays child records that are linked to the parent record through a relationship field. The relationship is always created on the child object: for example, a lookup or master-detail field on the Case object pointing to Account makes Cases appear as a related list on the Account record. Key facts to remember:
- A related list is generated automatically when you create a lookup or master-detail field, as long as you leave the Add Related List checkbox selected during field creation and choose the page layouts to add it to.
- The Related List Label is set on the relationship field definition (for example, you can rename the list of child records from the default plural label to something more meaningful such as 'Service Requests').
- Standard objects come with many standard related lists (Contacts, Opportunities, Cases, Open Activities, Activity History, Notes and Attachments, Files, Account History, Campaign History, and so on). Some of these have prerequisites: the History related list only shows data when field history tracking is enabled for the object and for the specific fields.
- Related lists only display records that the running user is allowed to see. Object permissions, field-level security and the sharing model all apply. Child records in a master-detail relationship inherit sharing from the parent, whereas lookup children have their own sharing settings, which is a frequent source of 'why can one user see the related record and another cannot' questions.
- Junction objects in a many-to-many relationship appear as a related list on both parent objects.

How Related Lists Are Configured on the Page Layout
The classic page layout editor remains the foundation for related lists in both Salesforce Classic and Lightning Experience. From Object Manager, open the object, go to Page Layouts, select the layout and use the Related Lists palette category. Here you control:
- Which related lists appear and in what order (drag and drop).
- Columns: click the wrench icon to open Related List Properties and choose up to 10 fields to display. You can include fields from the child object and, for some relationships, fields from related lookup objects. Fields hidden by field-level security are not displayed even if added to the layout.
- Sort order: choose one field and ascending or descending order.
- Buttons: show or hide standard buttons (such as New) and add custom list buttons created on the child object. If a custom button must perform a mass action on selected records, the button must be defined as a List Button with the Display Checkboxes (for Multi-Record Selection) option enabled.
- Apply column information to other page layouts: a time saver when the same related list exists on multiple layouts of the same object.
Because page layouts are assigned by profile and record type, you can give different user groups different related lists simply by using different layouts. In Classic you can also enable Related List Hover Links under User Interface settings so that users see a row of links at the top of the record with record counts.
A critical limitation to remember: a standard related list on a page layout cannot filter which records appear. It always shows all accessible child records of that relationship. If a scenario asks to show only Open Cases or only Closed Won Opportunities, the page layout alone cannot do it.

How Related Lists Are Configured in Lightning App Builder
Lightning Experience adds several components that give administrators much more flexibility. On a Lightning Record Page you can use:
- Related Lists: displays all related lists defined on the assigned page layout in the layout order. You can choose between the Basic List and the Enhanced List type. Enhanced related lists display up to 10 columns, let users resize and sort columns, wrap text, perform mass actions on selected rows, and show more records before requiring View All.
- Related List - Single: shows one specific related list chosen from the page layout. You can set the number of records to display, pick the list type (Basic or Enhanced), hide the header, hide action buttons, and set component visibility filters. This lets you place a critical list such as Open Activities in a prominent tab or sidebar region.
- Dynamic Related List - Single: the most powerful option. It does not depend on the page layout. You select the related object (the relationship), define filter criteria so that only matching records appear (for example Status equals Open), choose up to 10 fields as columns, set sort order, choose how many records to display, and give the list its own label. This is the standard answer whenever a question requires a related list that shows only a subset of child records or shows the same child object twice with different filters (such as Open Cases and Closed Cases as two separate lists on one page).
- Related List Quick Links: shows the related lists as compact links with record counts; hovering displays a preview of the records. This is ideal when a page is crowded and users want quick navigation rather than full tables.
- Related Record and Record Detail are not related lists, so do not confuse them; Related Record displays the fields of a single parent record (for example the parent Account on a Contact), not a list of children.
All of these components support component visibility filters, so you can show or hide a related list based on field values on the record, the device form factor, user permissions or profile. Changes made in Lightning App Builder affect only the Lightning record page they are made on, and the page must be activated and assigned (org default, app default, or app plus record type plus profile) before users see it.

Behavior and Limits Worth Memorizing
- Maximum of 10 columns per related list, both on page layouts and in dynamic related lists.
- Related lists on the record page show a limited preview; View All opens the full list, which in Lightning supports column sorting and, for enhanced lists, inline editing of editable fields.
- Activities in Lightning Experience are typically shown in the Activity Timeline rather than the Open Activities and Activity History related lists, although those lists can still be added.
- Notes and Attachments versus Files: the Files related list is the modern Lightning option; Notes and Attachments is legacy.
- Lookup filters restrict which records a user can select in a lookup field; they do not filter what appears in a related list.
- Deleting a lookup or master-detail field removes the corresponding related list.
- Changing the related list label on the relationship field changes it everywhere; renaming in a Dynamic Related List - Single changes only that component.
- On the Salesforce mobile app, related lists appear on the Related tab of the record and follow the same layout and Lightning page configuration.

Exam Tips: Answering Questions on Related Lists and Related List Configuration
1. Match the keyword to the tool. If the scenario says 'show only certain records' or 'filter the related list', the answer is Dynamic Related List - Single. If it says 'add a field as a column', 'change the order of columns' or 'change the sort', the answer is Related List Properties on the page layout. If it says 'show counts and preview on hover', think Related List Quick Links (Lightning) or Related List Hover Links (Classic). If it says 'resize columns, inline edit or mass actions', think Enhanced Related List.
2. Remember the 10-column limit. Any option promising 12 or 15 columns in a related list is a distractor.
3. A missing related list is a troubleshooting question. Check, in order: does the relationship field exist, is the list on the assigned page layout, is the Lightning page activated and assigned correctly, does the user have object permission on the child object, and does the sharing model grant access. Field-level security hides columns, not the whole list.
4. A missing button on a related list means the custom list button was created on the child object but not added in Related List Properties on the parent layout, or the button was created as a detail page button instead of a list button. Mass actions require the multi-record checkbox option.
5. Different users need different related lists is solved with page layout assignments by profile and record type, or with component visibility filters in Lightning App Builder. Do not jump to code.
6. Same child object shown twice (for example Open and Closed Cases) requires two Dynamic Related List - Single components with different filters; a page layout can contain a given related list only once.
7. History related list shows nothing means field history tracking is not enabled; it is not a page layout problem.
8. Sharing nuances: master-detail children inherit parent access, lookup children do not. If one user sees fewer related records than another, suspect sharing rules or organization-wide defaults on the child object, not the related list configuration.
9. Eliminate answers involving Apex, Visualforce or custom Lightning Web Components when a declarative component can meet the requirement. The exam rewards the simplest supported configuration.
10. Read for scope words such as 'in Lightning Experience', 'on the mobile app' or 'in Salesforce Classic'. Dynamic related lists and Quick Links exist only in Lightning Experience; hover links are a Classic setting.

Summary
Related lists are generated by relationship fields on child objects and surfaced on record pages. The page layout controls which lists exist, their order, their columns (up to 10), sort order and buttons. Lightning App Builder layers on the Related Lists, Related List - Single, Dynamic Related List - Single and Related List Quick Links components, with Enhanced list styling, record-count limits, filters and component visibility. Security always governs what a user ultimately sees. When answering exam questions, identify the exact requirement, map it to the single tool designed for it, and rule out options that exceed known limits or require code.