After reading a couple of low reviews saying theirs had blown over, we screwed it securely to the fence and floor and up to now even with quite a strong breeze we haven't had any problems.  Feels like we are on holiday and we have sat outside for much longer than when we had no shade apart from an umbrella.  Very happy customer, I am very pleased we have purchased this.  Anyone buying this just make sure you secure it to a fence and the floor.