The UK Inhaler Group (UKIG) has produced a practical concise guide to support healthcare professionals in selecting and using spacer and valved holding chamber (VHC) devices for patients with asthma and COPD. Appropriate spacer/VHC selection and use can improve drug delivery, optimise disease control, and reduce treatment-related side effects. The guide highlights that selecting the right spacer matters just as much as choosing the right inhaler and that the best device is one a patient can and will use. This can lead to improved symptom control, fewer exacerbations and reduced treatment related side effects. This guide aims to support clinicians in making informed, patient-centred decisions that optimise both technique and treatment outcomes.