An apparatus for providing positive airway pressure, comprising: a blower configured to provide pressurized air to a patient interface; a controller configured to: control an air pressure provided by the blower at a first therapeutic pressure treatment level during a first treatment session; detect the occurrence of sleep disordered breathing events during the first treatment session and determine and record an Apnea Hypopnea Index; and adjust the first therapeutic pressure treatment level in response to the detected SDB events during the first treatment session; in a setting procedure, determine a second generally constant therapeutic pressure treatment level to be provided in a second treatment session, the second treatment session being subsequent to the first treatment session, the second generally constant therapeutic pressure treatment level being determined based on checking the date and/or time of an internal clock and the recorded AHI in the first treatment session; and maintain the air pressure at the second generally constant therapeutic pressure treatment level without changing the therapeutic pressure treatment level during the second treatment session, and wherein the first treatment session comprises at least one sleep session and the second treatment session comprises a different sleep session. a blower configured to provide pressurized air to a patient interface; a controller configured to: control an air pressure provided by the blower at a first therapeutic pressure treatment level during a first treatment session; detect the occurrence of sleep disordered breathing events during the first treatment session and determine and record an Apnea Hypopnea Index; and adjust the first therapeutic pressure treatment level in response to the detected SDB events during the first treatment session; in a setting procedure, determine a second generally constant therapeutic pressure treatment level to be provided in a second treatment session, the second treatment session being subsequent to the first treatment session, the second generally constant therapeutic pressure treatment level being determined based on checking the date and/or time of an internal clock and the recorded AHI in the first treatment session; and maintain the air pressure at the second generally constant therapeutic pressure treatment level without changing the therapeutic pressure treatment level during the second treatment session, and control an air pressure provided by the blower at a first therapeutic pressure treatment level during a first treatment session; detect the occurrence of sleep disordered breathing events during the first treatment session and determine and record an Apnea Hypopnea Index; and adjust the first therapeutic pressure treatment level in response to the detected SDB events during the first treatment session; in a setting procedure, determine a second generally constant therapeutic pressure treatment level to be provided in a second treatment session, the second treatment session being subsequent to the first treatment session, the second generally constant therapeutic pressure treatment level being determined based on checking the date and/or time of an internal clock and the recorded AHI in the first treatment session; and maintain the air pressure at the second generally constant therapeutic pressure treatment level without changing the therapeutic pressure treatment level during the second treatment session, and wherein the first treatment session comprises at least one sleep session and the second treatment session comprises a different sleep session.