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+# Contributing to Iconify icon sets
+
+Icon set `.json` files are automatically generated.
+
+Pull requests with icon sets are not accepted.
+
+Pull requests with fixes and updates to other files are welcome.
+
+## Icon sets
+
+If you want to suggest an icon set to add, please create an issue.
+
+Issues for icon sets are welcome.
+
+## Limitations
+
+Not all icon sets are accepted.
+
+There are many thousands of icons available, but that does not mean they are useful. 
+Iconify is not a collection of random SVG files.
+
+Requirements for icon sets:
+- Only open source icon sets are accepted.
+- Icons must be usable in UI elements, such as buttons and navigation. High detailed illustrations are not accepted.
+- Icon set must be usable. Random stuff, such as car logos and icons specific to your website, do not belong here.
+
+Additionally, the following restrictions apply to most icon sets, but exceptions can be considered on case by case basis:
+- Icons with hardcoded palette are rarely accepted because of their limited use. Icons designed for specific apps, such as desktop themes, are not really usable and therefore not accepted.
+- Icon sets are automatically kept up to date. In order to keep icon sets up to date, SVG files must be easily available where download can be automated. See below.
+
+If you are not sure if an icon set can be added, just open an issue.
+
+### Sources
+
+In order to keep icon sets up to date, icon sets must be available wherever it is possible to automate download.
+
+Examples:
+- Git repositories
+- Figma files (can be accessed with API)
+- NPM packages
+
+Downloading icons from a website is not an option.
+
+## Consistent UI
+
+While requirements listed above might seem to be strict, they are there for a reason.
+
+When developer creates a UI, icons should have the same layout. If they don't, website looks ugly.
+
+It is preferrable to have icon sets with large choice of consistently designed icons.
+
+## Why not all SVGs are accepted?
+
+There are many thousands of badly designed icons that are not wanted. 
+All those icons do, is make it harder to find good usable icons.
+
+If you just want to find one specific icon, do not care if it is a part of set, there are plenty of websites out there that collect all possible SVGs from the internet. 
+Iconify project is not one of them.
+