One of the big differences you will find between IPSC matches depends on what level of sanctioning they receive.
Level I matches are informal Club Matches. Generally, they do not require pre-registration or current membership with IPSC. Competitors must have successfully completed a Black Badge Training course in order to participate in a Level I match. Most clubs do not make organized shooting schedules for Level I matches, but do ask that competitors arrive early in the day for registration and so that they may receive their score cards for the match.
Level II matches in BC are referred to as Qualifiers. Pre-registration is required, and shooters are usually required to spend the whole day at the range following a set, organized shooting schedule. Competitors must be current members in good standing of IPSC, although they may be from other Provinces or Countries. Scores from Qualifier matches are recorded and used to track shooter Classification, upon which awards are based.
Level III matches are a rarity. To achieve Level III sanctioning, the match must be approved by both the Regional Directorate for Canada and by the IPSC World Body. The match must adhere to strict standards and guidelines established by IPSC. Match winners of Level III matches, and winners of special categories (Juniors, Ladies, and Seniors) win President's Medals - an accomplishment for any competitive shooter. Not many matches are designated as Level III. These include Provincial and National Championships and some special matches which the Match Directors have decided to do the extra work for.
An IPSC style match is usually comprised of several stages. Each stage (sometimes referred to as a Course of Fire or COF) consists of several paper or steel targets. During an IPSC match, a competitor will shoot all of the individual stages. Match Points are awarded based on the placement of each shooter relative to the stage winner. The highest Match Point total is declared the winner, and the remaining shooters scored as a percentage of the winner.
When shooting an IPSC match, expect to be on the range for several hours, both waiting for your turn to shoot, and helping to tape targets and set steel. This downtime, however, is a blessing. It allows you the opportunity to meet new people and interact with people who have a common love of shooting.