> ## Documentation Index > Fetch the complete documentation index at: https://docs.tackstudio.co/llms.txt > Use this file to discover all available pages before exploring further. # Align to > Choose what your layers align relative to. Every action in Align Pro (align, distribute, and distribute spacing) is measured against a target you choose first. This is the **Align to** control at the top of the panel, shown as either a row of icon buttons or a dropdown menu depending on your [panel preferences](/align-pro/preferences). | Target | Aligns/distributes relative to... | | ----------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Composition | The composition frame. | | Outside | The same as Composition, but layers land just outside the frame edges instead of flush against them. Handy for positioning layers off-screen before or after a slide in/out. | | Selection | The combined bounding box of your current selection. | | Key Layer | The first layer you selected (the **key layer**). Every other selected layer moves; the key layer never does. | | Title Safe | After Effects’ title-safe margin, set in **Preferences > Grids & Guides**. Hold **Alt**/**Option** while clicking an align or distribute button to use the action-safe margin instead. | Some Align to targets disable specific buttons or modifiers that wouldn’t make sense together. For example, Outside disables centering, since "outside" is only meaningful at an edge. See [Modifiers](/align-pro/modifiers#some-combinations-are-disabled).