Airway clearance is integral to the management of bronchiectasis, yet there is no evidence as to the optimal modality. The aim of this randomized prospective study was to evaluate the acute efficacy, acceptability and tolerability of three airway clearance techniques in non-cystic fibrosis (non-CF) bronchiectasis. Flutter, active cycle of breathing technique (ACBT) and ACBT with postural drainage (ACBT-PD) were evaluated in random order over a week in 36 patients (mean age 62 years, range 33-83), with stable non-CF bronchiectasis. Total sputum wet weight for ACBT-PD was twice that of either ACBT alone or Flutter. No objective difference in treatment duration was noted. All three techniques were well accepted and tolerated. Patient preference was 16 (44%) for Flutter, eight (22%) ACBT and 12 (33%) for ACBT-PD. Patient demography, factors such as upper airways or reflux symptoms, previous use or acute efficacy did not predict preference. This is the first randomized systematic evaluation of acute efficacy, acceptability and tolerability of Flutter, ACBT and ACBT-PD in non-CF bronchiectasis. All three techniques were well tolerated but ACBT-PD proved superior in terms of acute efficacy. Patient preference for treatment modality could not be predicted.