(CNN) -- Dr. Bernard Kaminetsky sees about a dozen patients during a typical day at his Boca Raton, Florida, practice. His patients have his personal phone number and can schedule a same-day appointment with him. Kaminetsky left his traditional practice in 2001 to join MDVIP, one of the leaders in the small but growing trend toward concierge, or boutique, medicine -- highly personalized care for patients who pay an annual fee.

Patients pay from $1,500 to $1,800 per year to join MDVIP. In exchange, they get a full physical and wellness plan, 24/7 access to their doctor, wallet-sized CDs with their medical data recorded on it and other services.

If firms like MDVIP are the Cadillac of health care, then MD2 (pronounced "M-D-Squared") is the Bentley -- offering unlimited access to patients who can afford it.

"Imagine if your brother, your father, or your mother was a physician and you became ill, that's what we provide," said MD2 partner John Moses.

Each MD2 doctor treats no more than 50 families, Moses said.

"What that means is that our physicians have all the time necessary to provide complete access to their patients, extraordinary care and service, and home or office visits," Moses said. "We're able to offer total privacy because it's highly unlikely that we would ever have more than one patient at our office at any given time."