Behaviourism is the theory or doctrine that human or animal psychology can be accurately studied only through the examination and analysis of objectively observable and quantifiable behavioural events, in contrast with subjective mental states. A dog practitioner using a behavioural approach, regardless of title, typically works one-on-one with a dog and its owner. This may be carried out in the dog's home, the practitioner's office or the place where the dog is showing behavioural problems or a variety of these locations for different sessions during the treatment time. By observing the dog in his/her environment and skillfully interviewing the owner, the behaviourist creates a working hypothesis on what is motivating, and thus sustaining, the behaviour. Office bound behaviourists may be disadvantaged when it comes to assessing behavioural modification, as the dog may act very differently in different locations and interviewing owners, no matter how thorough, may not provide enough details. After establishing a motivating cause, the practitioner will develop a step-wise, goal-based plan to alter the behaviour in stages, continue their work with the pet owner to guide and make changes in the plan as the goals are met (or not) and conclude with a final write up of the case and its outcome.