Objectives: The aim of this study was to evaluate the outcome of a package of evidencebased person-focused training for formal carers working with people with dementia living in care homes. Specifically evaluating the efficacy of a new Formulation based Functional Analysis (FFA) approach to understanding stress and distress behaviours (SAD-behaviours) with dementia. Design: The study employed an open trial design, with three independent groups: two training interventions and a waiting list control. Method: Forty eight care staff were recruited from care homes across Cambridgeshire. Participants in intervention group one attended 15 hours of training (CAMTED), participants in intervention group two attended 21 one hours of training including a FFA module in understanding SAD-behaviours (CAMTED-Plus). The waiting list control consisted of staff waiting to receive training. All participants completed outcome measures on knowledge and attitudes to dementia, burden, job satisfaction and perceived frequency of SAD-behaviours and confidence in managing SAD-behaviours at baseline and post-intervention. Results: Due to the small sample size the waiting list group was excluded from data analyses. Results showed that there were no statistically significant differences between CAMTED and CAMTED-Plus on any of the outcomes at the end of the intervention. Within-group analyses of pre-post change found statistically significant differences for CAMTED in the degree of hopefulness about dementia and CAMTED-Plus in attitude to dementia, extent to which a person-centred approach is adopted and levels of depersonalisation. Positive feedback was provided on the use of the jigsaw training tool and verbal feedback indicated participants’ positivity about the training. Conclusion: The results provide preliminary support for the utility of the FFA approach as a training intervention. Although the results are limited due to the methodological shortcomings, they provide a range of evidence in support of the FFA approach, which may be built on in the future.