# Relationship Links
{% hint style="info" %}
**Who can use this feature?**
Task Owners, Assignees and Admins can add relationship links between tasks
{% endhint %}
Relationship Links in Aphex allow you to establish task dependencies, ensuring tasks are completed in the correct order. Whether you need tasks to start together, finish together, or follow one another, Relationship Links help keep your project on track and aligned.
## Drawing Relationship Links
***
You can draw links directly on the Gantt - just click and drag from one bar to another. The link type is set based on where you start and end. It’s quick, visual, and often the easiest way to build out your logic as you go.
#### **How to Draw a Relationship Link:**
* Hover over the Predecessor Task Bar and click the
* Click and drag from the predecessor to the successor
* Release the mouse to automatically create the relationship.
Link Type and Direction
| Direction | Visual | Explainer |
| ------------------------ | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------ |
| **Start > Start (SS)** |  | The second task starts when the first task starts. |
| **Start > Finish (SF)** | .svg?alt=media\&token=2f9dd4f6-e26e-4e7a-b64b-77aad29775b0) | The second task finishes when the first task starts. |
| **Finish > Start (FS)** |  | The second task starts when the first task finishes. |
| **Finish > Finish (FF)** |  | The second task finishes when the first task finishes. |
Scheduling Behaviour
* Moving a driving task will reschedule all dependent successors in the chain
* Tasks won’t lose their link logic - rescheduling respects the original structure
* Updates happen in real time as you adjust dates, add delays or drag bars on the Gantt
## Highlight Linked Tasks on the Gantt
***
Spotlight Mode helps you quickly see how a task connects to the rest of the plan.\
Instead of manually tracing arrows or opening extra panels, you can highlight a task and follow its linked pathway directly on the Gantt, with hints showing where the sequence continues off screen.
#### Turn on Spotlight Mode
* Select a Task Bar on the Gantt
* Click the Spotlight Button that appears next to the Task
* The linked pathway will be highlighted immediately
#### Use pathway hints
* Look for the small Pathway Hint tags at the edges of the screen
* These show how many linked Tasks sit just out of view
* Click a hint to preview the linked Tasks or jump directly to them
#### Exit Spotlight Mode
* Click the `X` in the banner
* Refreshing the page or logging out will also disable Spotlight Mode
Spotlight Mode Behaviour
**While Spotlight is active**
* Clicking another task switches the spotlight to that pathway
* Up and down arrow keys change the spotlighted task
* You can pan, scroll, and switch Views without disabling Spotlight
* All normal task interactions remain available
**Selection behaviour**
* Spotlight follows the currently selected Task
* Clicking into empty space deselects the Task and clears the Pathway Spotlight
**Printing**
* Spotlight is not included in print outputs
* Printing does not disable Spotlight
* Returning to the Gantt keeps Spotlight active
## Linking Multiple Tasks
***
Checkboxes let you select multiple Tasks and build logic between them all at once. Set the sequence, adjust the link type & lag, and apply. It’s the fastest way to build out a full section of your plan.
#### **To Link Multiple Tasks:**
* Hover over tasks and click 
* Click the Link icon in the multi-select toolbar
* Choose the link type (`SS`, `SF`, `FS`, `FF`), add any lag if needed and confirm
## Link Search
***
If the Task you want to link to isn’t visible, drop your link on the blue search icon. A menu will open so you can quickly search and select the right Task without changing your filters or losing your place.
#### **How to Link Tasks using the Link Modal:**
* Hover over the Predecessor Task and click the
* Click and drag to
* The Link Search Modal will appear. Use the search bar or filters to find the task you want to link
* Select the task, choose the link type, and apply the relationship
## Creating Links from a Specific Task
***
When you open a Task, you’ll see a full list of its linked Tasks including Link Type, Lag and Float/Driving. From here, you can make changes or add new relationships; no dragging or switching views required.
#### **Adding a Relationship Link from the Task Panel:**
* Open the Task Panel for the task you want to link.
* Scroll to Related Tasks and click
* The Link Search Menu will appear. Use the search bar or filters to find the task you want to link.
* Select the task, choose the link type, and apply the relationship.
## Add or Remove Lag
***
Lag lets you add a space between linked Tasks, helping account for handovers, wait times, or real-world gaps without shifting tasks manually. As you adjust Tasks, Aphex gives you a quick visual cue showing how much lag you’ve just added or removed.
#### **Add Lag to Relationship Links from the Gantt:**
* Use the `Task Bar`, or `Start` and `End` properties to edit the dates of the successor Task
* The Lag Change Indicator appears, showing the number of lag days added or removed
#### **Add Lag to Relationship Links from the Task Panel:**
* Open the Task Panel for the Task you want to link.
* Scroll to `Related Tasks` and click into the `Lag` field and enter a value
#### **Add Lag to Relationship Links from the Link Modal:**
* On the Gantt, click a Link Line
* In the `Link Modal`, click into the `Lag` field and enter a value
* Select to apply the Lag change to the relationship
Lag Rules
* The Predecessor Task Calendar is used to determine lag when added to a relationship link
* When drawing Links on the Gantt, Aphex automatically applies zero-day lag, snapping the successor to come immediately after the predecessor
* Hold `Shift` while drawing the link to keep the existing gap - Aphex will automatically calculate and apply the right lag to preserve the spacing between tasks
* The Lag Change Indicator will be visible on the Gantt for a few seconds after the change is applied
## **Identifying Driving Tasks**
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Each relationship between Tasks shows whether it’s Driving or how much Float it has.\
A Driving relationship means the predecessor has zero float - any change to it will move the successor.\
Links with float display how much flexibility exists before the successor is affected.\
\
These values update automatically as Task dates, link type, or lag change, helping you see which parts of the schedule are fixed and which still have room to move.
#### To reveal Driving Tasks & Float from the Gantt:
* Click any relationship link on the Gantt - single or multiple
* In the `Link Menu` that opens, Driving Tasks are marked with 
* Links that aren’t driving display their Float Value 
How Driving Tasks & Float are calculated
* **Float** is the amount of time a predecessor task can move without delaying its successor
* It’s calculated automatically using the **start and finish dates** of both tasks, the **relationship type**, and any **lag** that exists between them
* When **Float = 0**, the predecessor is considered **Driving** - any change to it will immediately shift the successor’s dates
* When **Float > 0**, the predecessor is **non-driving** and has flexibility before it impacts the successor
* Float and Driving values update **dynamically** whenever task dates, relationship types, or lag are changed
**Example**
* Predecessor task finishes on: **1 September**
* Successor task starts on: **6 September**
* Lag: **1 day**
* Assume all days are working days
**Step-by-step:**
* Days between 1 Sep and 6 Sept (inclusive): 5 days
* Float = 5 - 0 - 1 = **4 days**
The predecessor has 4 days of float. It can finish as late as **5 September** without delaying the successor
## Editing & Breaking Links
***
You can edit or break existing relationship links at any time to update or remove connections between Tasks.
#### **How to edit an existing Link:**
* On the Gantt, click a Link Line
* In the Link Modal that opens, you can either:
* edit the Link Type (FS, SF, FF, SS)
* edit the Lag
* Click to apply edits to the relationship
#### **Breaking Relationship Links:**
* On the Gantt, click a Link Line
* In the Link Modal that opens, click `Remove Link`
## **Understanding Scheduling Behaviour**
***
Understanding scheduling behaviour helps you predict how linked tasks behave when dates change based on whether they're Planned, Promised, or Done. It’s the key to controlling movement, Ripple Status, and Progress Updates in your plan.
{% tabs %}
{% tab title="If the Predecessor is Planned" %}
* **Successor is Planned:**
* Both tasks reschedule freely.
* Successor follows any changes to the Predecessor.
* **Successor is Promised or Done:**
* Successor won’t move.
* Only the Predecessor shifts.
{% endtab %}
{% tab title="If the Predecessor is Promised" %}
* **Successor is Planned:**
* Successor moves freely and reschedules based on new Predecessor date.
* **Successor is Promised:**
* You’ll get a Ripple Status prompt.
* Optionally apply the delay to the Successor.
* **Successor is Done:**
* Successor won’t move. Only the Promised Predecessor shifts.
{% endtab %}
{% tab title="If the Predecessor is Done" %}
* The task is locked. You can’t move it.
* Any changes must start from its Successors.
{% endtab %}
{% endtabs %}
See also: Task Status
.svg?alt=media&token=99817386-6953-431c-bb39-fd578ad1882c)
* Click and drag from the predecessor to the successor .svg?alt=media&token=d48704e3-3016-4c38-ad72-ef0e19bc123d)
that appears next to the Task
* The linked pathway will be highlighted immediately
#### Use pathway hints
* Look for the small Pathway Hint 
tags at the edges of the screen
* These show how many linked Tasks sit just out of view
* Click a hint to preview the linked Tasks or jump directly to them
#### Exit Spotlight Mode
* Click the `X` in the 
banner
* Refreshing the page or logging out will also disable Spotlight Mode
.svg?alt=media&token=592ffea6-2c2d-442c-94f2-c86bc55dbc16)
in the multi-select toolbar
* Choose the link type (`SS`, `SF`, `FS`, `FF`), add any lag if needed and confirm
## Link Search
***
If the Task you want to link to isn’t visible, drop your link on the blue search icon. A menu will open so you can quickly search and select the right Task without changing your filters or losing your place.
.svg?alt=media&token=29ab4889-8f83-4bf9-afb7-be2c68161d1d)
* Click and drag to 
* The Link Search Modal will appear. Use the search bar or filters to find the task you want to link
* Select the task, choose the link type, and apply the relationship
## Creating Links from a Specific Task
***
When you open a Task, you’ll see a full list of its linked Tasks including Link Type, Lag and Float/Driving. From here, you can make changes or add new relationships; no dragging or switching views required.
#### **Adding a Relationship Link from the Task Panel:**
* Open the Task Panel for the task you want to link.
* Scroll to Related Tasks and click 
* The Link Search Menu will appear. Use the search bar or filters to find the task you want to link.
* Select the task, choose the link type, and apply the relationship.
## Add or Remove Lag
***
Lag lets you add a space between linked Tasks, helping account for handovers, wait times, or real-world gaps without shifting tasks manually. As you adjust Tasks, Aphex gives you a quick visual cue showing how much lag you’ve just added or removed.
.svg?alt=media&token=6b3da9e2-f155-4ab3-9f76-28e44a110584)
appears, showing the number of lag days added or removed
#### **Add Lag to Relationship Links from the Task Panel:**
* Open the Task Panel for the Task you want to link.
* Scroll to `Related Tasks` and click into the `Lag` field and enter a value
#### **Add Lag to Relationship Links from the Link Modal:**
* On the Gantt, click a Link Line
* In the `Link Modal`, click into the `Lag` field and enter a value
* Select 
to apply the Lag change to the relationship
.svg?alt=media&token=9c5a94fa-cd37-4ec7-af95-ef062e53180f)