Greywater Reuse for Laundry

I am a research engineer at the Environmental & Water Technology Centre of Innovation and I am looking for ways to reduce water consumption and promote water reuse and recycling. 

Can greywater be recycled and reused for laundry? How should the water be treated beforehand and will the laundry be clean enough? 

In which countries is greywater reuse for laundry promoted and applied?