A large part of the mystery comes from the fact that there are few substantive measures of a sail's performance. How well a sail fulfills its mission and how long it lasts is a subjective judgment based on four hard-to-quantify factors: (1) the quality of its design and materials; (2) the sailing conditions; (3) its frequency of use; (4) the way the sail is used or abused. How do you find the sailmaker and the sail that's right for you?

While the march of technology has resulted in better sails, it's made choosing the right sail, and assembling an inventory that's right for your boat and your kind of sailing, more crucial than ever. In general, most sailors fit into one of three sail-use categories: weekender, cruiser/ racer, or bluewater, each with specific sail needs and priorities.

Weekender. If your sailing is limited to daysailing or close-to-home weekend use, it's likely that your time and money commitment to your boat are limited. Make low cost and ease of use your sail-buying priorities.

Cruiser/racer. Your cruising may run from local, weekend stuff to several-hundred-mile, weeks-long trips; your racing may range from club nights to race weeks to point-to-point races. Place your priority on sailing performance--sails that deliver top boatspeed over a wide range--and performance life--sails that keep their shape longer.

Bluewater. If your plans call for crossing oceans or spending months cruising breezy or high-ultraviolet areas, make ultimate life your top priority.

Here are guidelines for minimum sail inventories.

Weekender

Mainsail: woven-polyester crosscut (standard or economy-grade fabric); conventional battens; one reef; lazyjacks.
Headsail: 150 percent overlap woven-polyester crosscut (standard or economy-grade fabric); leech and foot ultraviolet covers.
Next sail to add: .75-ounce radial-head cruising spinnaker, with dousing sock.

Cruiser/racer

If you use your boat for both cruising and racing, make performance--in both sail shape and shape longevity--a priority when assembling your boat's sail inventory. Here are guidelines for a minimum sail wardrobe.
Mainsail: woven-polyester crosscut (standard or high-tenacity fabric, fill-oriented); full-length battens or top-two-full battens; two reefs; lazyjacks or Dutchman system (racing emphasis) or built-in sail cover (cruising emphasis).
Headsail: radial-paneled laminate or fiber-oriented (racing emphasis), 135 percent (cruising) or racing-specific overlap; foam luff flattener; head and tack reefing patches or extended reinforcing; leech and foot ultraviolet covers (cruising emphasis).
Cruising spinnaker: .75-ounce, triradial construction, dousing sock.
Storm jib.
Next sail to add: non-overlapping roller-reefing/furling laminate jib with foam luff flattener.

Bluewater

When buying a sail inventory for bluewater cruising, place your emphasis on durability.
Mainsail: woven-polyester crosscut (high-tenacity, fill-oriented fabric, 1 ounce heavier than standard); either full-length battens (if the budget can include a top-quality luff-car system) or (if the boat can afford a reduction in mainsail area) battenless; two reefs; extended two-ply head and clew areas; triple-stitched, "Seam-kote" (plastic coating) seams; extra reinforcing in batten areas, tablings, and luff and foot slides; top-quality hardware; the most "bulletproof" furling system.
Primary headsail: woven-polyester crosscut (high-tenacity fabric, 1 ounce heavier than standard), 135 percent overlap; triple-stitched, "Seam-kote" seams; two-ply head and clew areas; extended patching or head and tack reefs; extra reinforcing in leech and foot tablings; foam luff flattener.
Jib or staysail: woven-polyester crosscut (high-tenacity fabric, 1 ounce heavier than standard); extra reinforcing; foam luff flattener. Storm trysail and storm jib: two-ply sections along leech.
Cruising spinnaker: triradial construction, .75-ounce with 1.5-ounce luff panels (or entirely 1.5-ounce, depending on expected use).
Next sail to add: depends on your budget and your cruising plans (whether you'll cruise trade-wind or high-latitude areas).