Aim: To explore factors influencing the delay in reporting symptoms of lung cancer and to develop an early reporting tool that would prompt people to report symptoms early and request a chest X-ray. Method: An expert panel of 16 healthcare professionals, lung cancer survivors and lay representatives was established to discuss the content and format of a possible early reporting tool. Six focus groups were held with 39 healthcare professionals and members of the public to explore factors influencing the delay in reporting symptoms and to develop the tool. Findings: The study revealed poor knowledge of lung cancer symptoms. Issues that influenced delay in reporting symptoms included a tendency to attribute other meanings to the symptoms, self-management of cough and fear of healthcare professionals’ attitudes, for example blame and stigma associated with smoking. Conclusion: Early presentation and assessment for treating lung cancer can improve survival. However, there seems to be a delay between patients noticing symptoms and reporting them to a doctor. Nurses play a key role in helping people overcome barriers to reporting possible lung cancer symptoms. Information interventions such as the one developed in this study could support nurses in this work.