Depression and anxiety are common in MS and often go untreated. Even symptoms which do not meet the threshold for a psychiatric diagnosis can have a significant impact on quality of life. Positive Mental Training (PosMT) is a 12 week programme which aims to help people overcome the negative thinking and feelings that come with worry and low mood and become more positive, confident and resilient. To find out if Positive Mental Training is helpful in MS the investigators are running a randomised controlled trial. The initial study is a pilot tiral, the primary function being examination of the feasibility and acceptability of this treatment in MS. Though sample size is small and consequently it may not be powered to detect a significant change in symptoms in association with the treatment, this will also be examined.

Psychiatric disturbance is common in multiple sclerosis (MS), with anxiety and depression the most frequent diagnoses. The lifetime rate of major depression is up to 50%. However, even symptoms of mood and anxiety which are not severe enough to warrant a diagnosis of a psychiatric disorder can still have a big impact people's lives. The investigators want to find ways to make people with MS feel better and cope better in their day to day life, and to be stronger inside themselves so that they don't become worried or stressed so much in the future. Positive Mental Training (PosMT) is a 12 week programme which aims to help people overcome the negative thinking and feelings that come with worry and low mood and become more positive, confident and resilient. To find out if Positive Mental Training is helpful in MS the investigators are running randomised controlled trial. Patients with MS who score higher than 4 on either the Hospital Anxiety (HADS-A) or Depression Scale (HADS-D) will be admitted to the trial. They will be randomly allocated to either an intervention or control group. The intervention group will be given the treatment immediately, the other 12 weeks later. In addition to the HADS, patients will be asked to complete two further questionnaires asking about how low mood and anxiety affecting them, both when they enter the trial and 12 weeks later. These are the Short Warwick-Edinburgh Mental Well-being Scale (SWEMWBS) and EuroQol health related quality of life - 5 dimensions - 5 levels (EuroQol-5D-5L). The primary function of this pilot trial is to ascertain suitability and acceptability of this treatment for people with MS, and to guide planning of a subsequent full trial. Feedback will therefore be obtained from participants in the treatment group of their experience of using the intervention. Though the sample size of this pilot trial is small, by comparing the change in scores on rating scales in patients given the treatment to those who have not been given it yet (the control group), it may be feasible to ascertain if PosMT is a useful treatment in MS.

Inclusion Criteria:

• Have confirmed diagnosis of Multiple Sclerosis

Exclusion Criteria:

• Lack capacity to provide informed consent
• Judged by the treating clinician to have cognitive deficits of such severity to preclude engagement with the treatment
• Felt by the treating clinician to be unsuitable to participate on other clinical grounds (e.g. significant receptive aphasia) will be excluded.
• Do not speak English (they would be unable to independently make use of the intervention)