Separation anxiety is common. Many dog owners do not seek help from a veterinarian but might consult a trainer. The objective of this study was to investigate Australian trainers’ opinions about separation anxiety. An online survey was distributed via training organisations, resulting in 63 completed surveys. Descriptive statistics and Fisher’s exact tests were applied. Respondents were grouped into reward-based (n = 41) and balanced (n = 22) trainers. Most trainers (82.5%) used multiple methods to identify separation anxiety but only 7.9% referred to a veterinarian for diagnosis. Reward-based trainers ranked assistance from a veterinarian and owner’s willingness to try medication as more important than balanced trainers (p < 0.05). More balanced trainers reported that medication was rarely necessary in the cases they saw: 50% balanced compared with 4.9% reward-based trainers, with 95% CIs of [28.2, 71.8] and [0.6, 16.5], respectively. Almost all (95.5%) balanced trainers believed separation anxiety was preventable compared with 52.6% of reward-based trainers (p < 0.05). We conclude that opinions about separation anxiety varied between reward-based and balanced trainers. Trainers are not taught, expected, or legally allowed to diagnose anxiety disorders. This study showed that balanced trainers were less likely to recommend involvement of veterinarians who can make a diagnosis and rule out other causes of observed behaviours.