Unless you're literally living in a cave (like a monk), you would have noticed the practice of mindfulness booming in all areas of modern life. Of course, mindfulness has been around in some form or another for thousands of years. While definitions vary, from the perspective of modern neurobiologically research, the skill of mindfulness is basically seeking some sort of present moment focused awareness, and usually having an anchor or focus of attention to achieve this end.
When introducing mindfulness as a concept, I usually give my quick and dirty take on the three main aims for the practice:
1. to break the pattern of whatever thought stream is happening in your mind by focusing on a safe, neutral stimulus, either something internal (e.g., the breath) or something external (e.g., sounds).
2. to develop somatic awareness;
3. using the first two benefits and through repeated practice to achieve some sort of regulated emotional state.
This is probably a massive oversimplification, but if you want to get technical I usually point people to some good books on the topic. Now, spiritual meditation is a different beast. I’m not a spiritual meditator so I’m not speaking from personal experience, but from my research, it seems to be about connecting with something more higher and more substantial power than the individual self. So what would happen if a client started seeing a professional Psychologist with an interest in mindfulness-based interventions, and a meditation teacher interested in spiritual enlightenment at once? Probably, what is destined to happen when science finds efficacy in an ancient practice, and takes it on as a therapeutic endeavour - you find people from diverse backgrounds doing what on the surface are similar techniques with different end goals.
Ultimately, I am hoping to give the client an experience that is different from ordinary consciousness with the ultimately goal being to help reduce their anxiety and alleviate depression by noticing and then changing or interrupting implicit internal patterns. On the other hand, the meditation teacher wants spiritual awareness and awakening. Both have merit, but one is definitely not my domain. While mindfulness skills are not a cure all, I've seen countless clients come in - particularly men - with significant anxiety and anger management challenges and benefit greatly from even a basic introduction to the practice. A lot of men already have a body-based practice where focus on the breath is part of the process (training at the gym, boxing, long-distance running to name a few). Bringing these skills to the table is a great bridge to mindfulness and training your mind to be focused isn't too much of a leap.