# Welcome to VST 3 SDK Interfaces
Here are located all **VST 3** interfaces definitions (including VST Component/Controller, UI, Test).
## License & Usage guidelines
More details are found at [www.steinberg.net/sdklicenses_vst3](http://www.steinberg.net/sdklicenses_vst3)
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Return to [VST 3 SDK](https://github.com/steinbergmedia/vst3sdk)