I never, ever, under any circumstances whatsoever, attach the lead to my dog’s collar - it’s very difficult to control a dog, even a small dog, with a lead attached to its collar, and there’s always the danger of neck-injury. In the case of a terrier who has a strong chase-instinct, it’s an ever-present danger.

We use a harness - Ruff-wear, Hurtta, or Dog-Copenhagen (we have all three) depending on where we’re taking him - all designed to prevent escape, and with a handle for close-control, and another for lifting him into the car, over stiles or other tall structures. Far better for the dog, and reassuring for the responsible owner.