For most deliveries the carrier will give you advanced notice by sending you email or text messages, keeping you updated as your parcel makes it's way to you. This also includes sending you an estimated delivery timeslot in many cases so you can arrange for someone to be home.
When delivering any of our standard items, if you're not in the courier will usually attempt to leave the parcel with a neighbour or in a secure location and they'll let you know (by email or leaving a card through your post box).
If there is nowhere safe to leave your parcel, they'll let you know they've attempted delivery & will try again, usually on the next day.
If your order is for heavy or large items (think large furniture or appliances) the courier will send you a message in advance to schedule the delivery.