Reactive dogs that lunge, bark or snap on lead are often experiencing fear or frustration rather than aggression, and respond well to behaviour modification focused on emotional state.
Reactive dogs suffer from chronic anxiety about their environment - the explosive behaviour owners find difficult is the dog's attempt to manage overwhelming fear or frustration. Using punishment to suppress this behaviour leaves the underlying emotional state unchanged and often worsens it. Evidence-based approaches that change the emotional response to triggers - through counter-conditioning and careful exposure below threshold - address the cause rather than the symptom. These take time and skill but achieve lasting welfare improvement. Dogs living with chronic anxiety deserve the investment in professional support and sometimes veterinary behavioural medication.