Dog training needs vary considerably based on the specific behaviour being addressed, and choosing between group classes and private one-on-one sessions should reflect the actual training goal rather than simply personal preference or convenience. Group classes work particularly well for basic obedience training and socialisation, since the presence of other dogs and people provides genuinely valuable exposure that private sessions alone cannot replicate as effectively. For more specific behavioural issues — aggression, severe anxiety, particular problem behaviours — private sessions generally allow a trainer to focus entirely on the individual dog's specific triggers and needs, providing more targeted intervention than a group setting permits. Ask any prospective trainer about their specific methodology, since training approaches vary considerably, and understanding whether a trainer uses positive reinforcement-based methods versus more traditional correction-based approaches matters for owners with specific philosophical preferences about training style. Trainer credentials and experience with your specific dog breed or behavioural concern deserve direct questions too, since general dog training experience does not always translate to expertise handling more specialised or challenging cases. For puppies specifically, early socialisation-focused group classes generally provide excellent foundational value, while addressing any specific behavioural concerns that emerge later in a dog's development often benefits from the more targeted approach private sessions provide.