# Journey entry sources, waits, random splits and joins

*Marketing Cloud Engagement Specialist Study Guide · Marketing Automation · Last updated October 29, 2026 · https://www.certifyforce.com/study-guide/marketing-cloud-engagement-specialist/marketing-automation/journey-entry-sources-waits-random-splits-and-joins*

How to pick the journey entry source from where the triggering action happens, which of the three core wait activities fits a timing requirement, and when a Random Split or a Join is the right flow-control activity, with Pause and Sales Cloud activities placed in context.

- Certification: Salesforce Marketing Cloud Engagement Specialist
- Exam section: Marketing Automation
- Study guide: https://www.certifyforce.com/study-guide/marketing-cloud-engagement-specialist

**Official exam objective:**

> Given a customer scenario, recommend the appropriate marketing automation solution.

## What the exam expects

- Recommend the entry source from where the triggering action happens: a Sales or Service Cloud record change, a CloudPages Smart Capture form, an action in a mobile app, an API call or a batch of data extension rows.
- Choose among Wait by Duration, Wait Until Date and Wait by Attribute given a timing requirement, and predict what happens when a contact arrives late or has no date.
- Use a Random Split to divide contacts by percentage regardless of data or behavior, and a Join to reunite branches so a shared activity is built once.
- Recognize when the answer is not an entry, wait or split at all: Pause for a temporary halt, or Lead and Task activities to create Sales Cloud records.
- Key terms: **entry source** (where contacts entering a journey come from); **entry event** (the action that prompts contacts to enter); **wait activity** (holds contacts before the next activity); **Random Split** (assigns paths at random by a chosen distribution); **Join** (merges contacts from two or more paths into one).

## Key facts

| Fact | Detail | Source |
|---|---|---|
| Salesforce Data Event | Sales or Service Cloud record created or updated; Flow Builder initiates the event | [Entry Sources](https://help.salesforce.com/s/articleView?id=mc_jb_entry_sources.htm&language=en_US&type=5) |
| CloudPages Form Submit Event | Uses a CloudPages Smart Capture form | [Entry Sources](https://help.salesforce.com/s/articleView?id=mc_jb_entry_sources.htm&language=en_US&type=5) |
| Mobile App Event | App actions such as install or purchase; filter on App Event data | [Entry Sources](https://help.salesforce.com/s/articleView?id=mc_jb_entry_sources.htm&language=en_US&type=5) |
| Contact Data Events | Not supported in an upcoming release; use Data Extension entry source | [Entry Sources](https://help.salesforce.com/s/articleView?id=mc_jb_entry_sources.htm&language=en_US&type=5) |
| Active entry source | Can't be edited; pause or stop, then create a new version | [Entry Sources](https://help.salesforce.com/s/articleView?id=mc_jb_entry_sources.htm&language=en_US&type=5) |
| Wait by Duration default | 1 day | [Wait Activities in Journey Builder](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_wait_activity.htm&language=en_US&type=5) |
| Wait by Attribute, date passed or missing | Contact proceeds immediately | [Wait Activities in Journey Builder](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_wait_activity.htm&language=en_US&type=5) |
| Random Split paths | Up to 10, assigned at random by the chosen distribution | [Split and Join Activities](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_split_join_activities.htm&language=en_US&type=5) |
| Join | Merges contacts from two or more paths into one | [Split and Join Activities](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_split_join_activities.htm&language=en_US&type=5) |
| Pause | Halts processing so a higher-priority campaign can run; resume later | [Journey Pause](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_pause.htm&language=en_US&type=5) |
| Lead and Task activities | Create or update Sales and Service Cloud records per contact | [Activity Types](https://help.salesforce.com/s/articleView?id=sf.mc_jb_activities_reference.htm&language=en_US&type=5) |

## Check yourself

- When can you edit an active journey's entry source?
- When does a contact skip straight past a Wait Until Date?
- How many paths can a Random Split have?
- Where are contacts stored when an API Event fires?

## Sources

- [Entry Sources](https://help.salesforce.com/s/articleView?id=mc_jb_entry_sources.htm&language=en_US&type=5)
- [Activity Types](https://help.salesforce.com/s/articleView?id=sf.mc_jb_activities_reference.htm&language=en_US&type=5)
- [Wait Activities in Journey Builder](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_wait_activity.htm&language=en_US&type=5)
- [Journey Builder Split and Join Activities](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_split_join_activities.htm&language=en_US&type=5)
- [Journey Pause](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_pause.htm&language=en_US&type=5)
- [Manage Customer Journeys](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_journey_types.htm&language=en_US&type=5)
- [Sales and Service Cloud Activities](https://help.salesforce.com/s/articleView?id=mktg.mc_jb_sales_service_cloud_activities.htm&language=en_US&type=5)
- [Get Started with Journey Builder](https://trailhead.salesforce.com/content/learn/modules/journey-builder-basics/get-started-with-journey-builder)

## About the full unit

The "Core concepts", "Exam traps" and "Worked scenario" sections of this unit, its 8 linked practice questions, and unlimited timed mock exams are included with the Marketing Cloud Engagement Specialist pack (USD $19): https://www.certifyforce.com/practice-exams