This study examined the experiences of parents receiving an autism spectrum disorder (ASD) diagnosis for their child. Mixed methods were used to give a detailed account of the sequence of events, parents' experiences and actions associated with the ASD diagnosis. Parents waited nearly two and a half years (mean = 28.72 months) before receiving the ASD diagnosis. Parents with lower general and autism-specific social support, poorer physical health functioning and children with more severe communication problems reported longer wait times. Surprisingly, parents reported more positive than negative experiences from receiving the diagnosis. Paediatricians and psychologists were consulted most frequently; paediatricians and general physicians were rated most likely to neglect early ASD symptoms and least likely to make appropriate referrals. Qualitative analyses revealed seven themes describing the parent experience during the diagnostic process: "heightened awareness", "initial search", "dissatisfaction with medical or associated processionals", "long process/delay", "feeling uninformed", "parent psychological and relational experiences" and "diagnosis goals". A set of commonly experienced stages characterising the process of obtaining a diagnosis were identified and formulated into a six-stage model of diagnostic delay adapted from the patients' health-seeking model.