It serves as a safe environment and source of support and treatment for users of street drugs - increasingly crack cocaine.
The charity is being renamed the Blenheim CDP as a result of a merger with the Community Drug Project, also based in London. Many of the staff from both organisations have qualified with health and social care NVQs. While these will have included units on drug work, few of their teaching sessions will have been specifically structured for drug workers.
Jo Palmieri, responsible for training at the Blenheim, says she regards this lack of focus on the reality of the drug workers' experience as one of the chief weaknesses of health and social care training programmes on offer. The course is seen by some as too far removed from the reality of drug work, making it harder to recruit and retrain people.
Ms Palmieri has developed a new 10-month NVQ course with Lynn James, who owns Quay Assessment Training, a private provider. It will run for the first time from January, providing NVQ level 3 (A-level equivalent) qualifications on a programme specifically for drug workers.
The core will cover areas such as communication, health and safety, and personal development. Each candidate will take on an additional four units of more specific skills.
What makes the training different is that the tutors, including those provided by Blenheim CDP itself, will have specialist knowledge of the drugs field and the students will be from the same area of work.
Ms Palmieri said: "The NVQ in health and social care includes drugs, but quite often they will find themselves in a room where most people are not working with drugs. So often the trainers would not have that specialist knowledge and the assessors would not be professionally competent in the drugs field. "
She is passionate about the abilities of the staff at the Blenheim. Many of them are former drug users. She said their special understanding of vulnerable people "is the main reason our clients keep coming back". Yet getting them to a level 3 qualification will not be easy in all cases, with some lacking basic schooling.
She said: "They will have to take responsibility for some of their own learning if necessary by going to college and catching up if they have no previous qualifications. But they will end up with a qualification to show for all the talent which we know they have."
The course is funded by Barnet College, a centre of vocational excellence for health.
Miss James has worked in the City, where she has seen drugs destroy the careers - and lives - of some high-flying professional people. She said: "I know from experience that, however clever you are, you can be vulnerable.
"We are not likely to make money out of this but I'm in the privileged position of being able to do a couple of things that I think are worth doing whether they make money or not."