A short 24-item version of the Five facet mindfulness questionnaire - the FFMQ-SF - is downloadable both as a Word doc and in PDF format.  

Mindfulness is currently a real focus for research, therapy and general interest.  To help discussion be constructive it's very important that we're clear what we're talking about, what we're trying to change, and whether we're being effective.  I wrote last year about "A new book: assessing mindfulness & acceptance processes in clients" and quoted Zindel Segal's review "Informed by the maxim that you can't study what you can't see, Baer's book provides the necessary psychometric underpinning to further our understanding of core change processes in mindfulness-based interventions".   

In 2006, Ruth Baer & colleagues published details of the "Five facet mindfulness questionnaire (FFMQ)" in their paper "Using self-report assessment methods to explore facets of mindfulness."  Subsequent research has further supported the FFMQ's value - see "Construct validity of the five facet mindfulness questionnaire in meditating and nonmeditating samples", "Psychological functioning in a sample of long-term practitioners of mindfulness meditation" and "Differential item functioning on the five facet mindfulness questionnaire is minimal in demographically matched meditators and nonmeditators".  The FFMQ has been used as a pre- and post- measure for participants on Mindfulness-based stress reduction courses and "Increases in mindfulness were found to mediate the relationships between formal mindfulness practice and improvements in psychological functioning, suggesting that the practice of mindfulness meditation leads to increases in mindfulness, which in turn leads to symptom reduction and improved well-being" - see "Relationships between mindfulness practice and levels of mindfulness, medical and psychological symptoms and well-being in a mindfulness-based stress reduction program."  

If you want to use the full 39 question version of the FFMQ, you can download it either as a Word doc and in PDF format.  However a 39 item scale - with five subscales and many items needing to be reverse scored - is fairly time consuming to use.  Last month, Ruth & colleagues published a shortened 24 item version of the FFMQ - an approximately 40% reduction in length.  The research is described in their paper "Psychometric properties of the five facet mindfulness questionnaire in depressed adults and development of a short form" which reported "In recent years, there has been a growing interest in therapies that include the learning of mindfulness skills. The 39-item Five Facet Mindfulness Questionnaire (FFMQ) has been developed as a reliable and valid comprehensive instrument for assessing different aspects of mindfulness in community and student samples. In this study, the psychometric properties of the Dutch FFMQ were assessed in a sample of 376 adults with clinically relevant symptoms of depression and anxiety. Construct validity was examined with confirmatory factor analyses and by relating the FFMQ to measures of psychological symptoms, well-being, experiential avoidance, and the personality factors neuroticism and openness to experience. In addition, a 24-item short form of the FFMQ (FFMQ-SF) was developed and assessed in the same sample and cross-validated in an independent sample of patients with fibromyalgia. Confirmatory factor analyses showed acceptable model fit for a correlated five-factor structure of the FFMQ and good model fit for the structure of the FFMQ-SF. The replicability of the five-factor structure of the FFMQ-SF was confirmed in the fibromyalgia sample. Both instruments proved highly sensitive to change. It is concluded that both the FFMQ and the FFMQ-SF are reliable and valid instruments for use in adults with clinically relevant symptoms of depression and anxiety."

The FFMQ-SF is downloadable here both as a Word doc and in PDF format.