Pilot Recency Requirements
The five-year recency requirement has been in place for a few years; the two-year requirement was introduced with the Canadian Aviation Regulations in October, 1996.

Five-year requirement
CARS 401.05 (1) No holders of a Canadian flight crew permit, licence or rating shall exercise the privileges of the permit, licence or rating unless:
(a) the holder has acted as pilot-in-command or co-pilot of an aircraft within the five years preceding the flight; or
(b) within the 12 months preceding the flight
(i) the holder has completed a flight review, in accordance with the personnel licensing standards, conducted by the holder of a flight instructor rating for the same category of aircraft;
(ii) the flight instructor who conducted the flight review has certified in the holder’s personal log that the holder meets the skill requirements for issuance of the permit or licence set out in the personnel licensing standards; and
(iii) the holder has successfully completed the appropriate examination specified in the personnel licensing standards. (Refer to “Recurrent Training” below.)

Two-year requirement
(2) No holder of a flight crew permit or licence, other than the holder of a flight engineer licence, shall exercise the privileges of the permit or licence in an aircraft unless the holder has;
(a) has successfully completed a recurrent training program in accordance with the personnel licensing standards (see “Recurrent Training” below) within the 24 months preceding the flight.
(b) in the case of an aircraft other than a glider or a balloon, where a passenger other than a flight test examiner designated by the Minister is carried on board the aircraft, has completed five night or day takeoffs and five night or day landings, if the flight is conducted wholly by day, or five night takeoffs and five night landings, if the flight is conducted wholly or partly by night.
(c) in the case of a glider, at least five take-offs and five landings in a glider, or two takeoffs and two landings in a glider with the holder of a flight instructor rating - glider and obtained a certification of competence to carry passengers on board a glider from that holder in accordance with the personnel licensing standards.

Six-month requirement: 
You cannot carry a passenger unless within the six months prior to the flight you have completed at least five takeoffs and landings in the same category and class of aircraft, by day or night if the flight is to be by day, and by night if the flight is to be by night.
Category means aeroplane, helicopter, etc., and class means single or multi-engine, land or sea.

Instrument ratings are valid for 24 months, but once 12 months have passed since the flight test, the six month rule applies: within six months preceding a flight under IFR, you must have acquired six hours of instrument time and completed six instrument approaches to Canada Air Pilot minimums.

Recurrent Training (CARS 421.05) 
(1) In order to comply with the requirements of 401.05(1)(b) [the five-year requirement]:
(a) the flight review shall include all items normally covered during the flight test for the issue of that permit or licence,
(b & d) the instructor completing the flight review shall certify in the holder’s logbook, “This is to certify that the skill requirement for ______ (permit or licence) has been met.” Include the date and the name, signature and licence number of the instructor.
(c) the holder shall successfully complete the written examination (PSTAR) for “Student Pilot Permit or Private Pilot Licence for Foreign and Military Applicants, Air Regulations.”
(2) In order to comply with the two-year currency requirements, any of the following are considered acceptable as recurrent training programs:
(a) completion of a flight review conducted by the holder of a flight instructor rating in the same category, including normal and emergency procedures and manoeuvres;
(b) attendance at a safety seminar conducted by Transport Canada Aviation;
(c) participation in a recurrent training program approved by the Minister which is designed to update pilot knowledge of human factors, meteorology, flight planning and navigation, and aviation regulations, rules and procedures;
(d) completion of a self-paced study program produced annually ( Click here for the Study) is designed to update pilot knowledge in subjects specified in (c) above. The completed copy shall be the most current published by date and shall be retained by the licence holders;
(e) completion of a mandatory 
training program or Pilot Proficiency Check as required by other Parts of the CARS;
(f) completion of the requirements for the issue or renewal of a pilot permit, licence or rating, including night, instrument, multi-engine, flight instructor, landplane or seaplane; or
(g) completion of the written examination for a permit, licence or rating.