Question: In ArcGIS Pro 1.3.1, I have just looked for the ability to start legend items in a new column.

This functionality is present in ArcMap's Legend Properties on the Items tab which appears below:

[![enter image description here](https://i.stack.imgur.com/c9p84.png)](https://i.stack.imgur.com/c9p84.png)

Has anyone found the equivalent functionality in ArcGIS Pro, or know when it may be expected to appear?

It is not mentioned in the [Work with a legend](https://pro.arcgis.com/en/pro-app/help/layouts/work-with-a-legend.htm) documentation.

Nor does it appear on the `Element: Legend Item` pane (see below)

[![enter image description here](https://i.stack.imgur.com/ymFCz.png)](https://i.stack.imgur.com/ymFCz.png)

Answer: 
This can be done in ArcGIS Pro 1.4 and I believe this is available even in 1.3.1.

1. Create a new legend.
2. Open the `Formal Legend` panel.
3. Click the `Legend Arrangement Options` button.

[![enter image description here](https://i.stack.imgur.com/mXAbom.png)](https://i.stack.imgur.com/mXAbom.png)

4. For `Fitting Strategy`, choose `Adjust columns and font size`. You can also specify the gap between columns under the `Spacing` section.

[![enter image description here](https://i.stack.imgur.com/qds6sm.png)](https://i.stack.imgur.com/qds6sm.png)

Note: if you choose `Adjust Columns` as your `Fitting Strategy`, then your legend will always have a new column for each item. However, I haven't found a property to specify the number of columns for the legend. You could work around this by resizing the legend item to force it to have a certain number of columns.

[![enter image description here](https://i.stack.imgur.com/751N8m.png)](https://i.stack.imgur.com/751N8m.png)

Your legend would look like this with the `Adjust columns and font size` strategy:

[![enter image description here](https://i.stack.imgur.com/ch5Qj.png)](https://i.stack.imgur.com/ch5Qj.png)

Your legend would look like this with the `Adjust columns` strategy:

[![enter image description here](https://i.stack.imgur.com/m0V66.png)](https://i.stack.imgur.com/m0V66.png)
In ArcGIS Pro 2.9, on the Format Legend/Legend Arrangement panel, select Manual Columns as the Fitting Strategy. Increase the number of columns if needed.

On the Contents/Drawing Order pane, the Column numbers appear with their layers indented. Drag and drop layers to move them to the top of a column.