The Temperament is unique for each breed. There is no certification for temperament. You got to trust your breeder in that one, but check on the parents (at least the mom). You should always be able to meet, play with, and interact with the parents, the mom and probably other family members of the puppies without a problem. Note that just whelped moms can be protective of their puppies and can sometimes turn aggressive on the first days after whelping. Labs must be friendly, alert, their short otter tails got to be wagging at all times. They might bark at the beginning to alert the new comer and their owners, but should be quiet shortly after. Here is what the standard says about the Labrador Retriever temperament:
“True Labrador Retriever temperament is as much a hallmark of the breed as the "otter" tail. The ideal disposition is one of a kindly, outgoing, tractable nature; eager to please and non-aggressive towards man or animal. The Labrador has much that appeals to people; his gentle ways, intelligence and adaptability make him an ideal dog. Aggressiveness towards humans or other animals, or any evidence of shyness in an adult should be severely penalized.”

Conformation Champion is not the only title you can put on a dog. There are  field champions, Hunting Champions, Agility Champions, working Dogs, Companion dog, etc.  The more titles the better.  Here is a list of the many other titles you can put on a dog:
http://www.akc.org/events/titles.cfm?page=2

General Appearance
The Labrador Retriever is a strongly built, medium-sized, short-coupled, dog possessing a sound, athletic, well-balanced conformation that enables it to function as a retrieving gun dog; the substance and soundness to hunt waterfowl or upland game for long hours under difficult conditions; the character and quality to win in the show ring; and the temperament to be a family companion. Physical features and mental characteristics should denote a dog bred to perform as an efficient Retriever of game with a stable temperament suitable for a variety of pursuits beyond the hunting environment.

The most distinguishing characteristics of the Labrador Retriever are its short, dense, weather resistant coat; an "otter" tail; a clean-cut head with broad back skull and moderate stop; powerful jaws; and its "kind," friendly eyes, expressing character, intelligence and good temperament.

Above all, a Labrador Retriever must be well balanced, enabling it to move in the show ring or work in the field with little or no effort. The typical Labrador possesses style and quality without over refinement, and substance without lumber or cloddiness. The Labrador is bred primarily as a working gun dog; structure and soundness are of great importance.

Size, Proportion and Substance
Size--The height at the withers for a dog is 22½ to 24½ inches; for a bitch is 21½ to 23½ inches. Any variance greater than ½ inch above or below these heights is a disqualification. Approximate weight of dogs and bitches in working condition: dogs 65 to 80 pounds; bitches 55 to 70 pounds.

The minimum height ranges set forth in the paragraph above shall not apply to dogs or bitches under twelve months of age.

Proportion--Short-coupled; length from the point of the shoulder to the point of the rump is equal to or slightly longer than the distance from the withers to the ground. Distance from the elbow to the ground should be equal to one half of the height at the withers. The brisket should extend to the elbows, but not perceptibly deeper. The body must be of sufficient length to permit a straight, free and efficient stride; but the dog should never appear low and long or tall and leggy in outline. Substance--Substance and bone proportionate to the overall dog. Light, "weedy" individuals are definitely incorrect; equally objectionable are cloddy lumbering specimens. Labrador Retrievers shall be shown in working condition well-muscled and without excess fat.

Head
Skull--The skull should be wide; well developed but without exaggeration. The skull and foreface should be on parallel planes and of approximately equal length. There should be a moderate stop--the brow slightly pronounced so that the skull is not absolutely in a straight line with the nose. The brow ridges aid in defining the stop. The head should be clean-cut and free from fleshy cheeks; the bony structure of the skull chiseled beneath the eye with no prominence in the cheek. The skull may show some median line; the occipital bone is not conspicuous in mature dogs. Lips should not be squared off or pendulous, but fall away in a curve toward the throat. A wedge-shape head, or a head long and narrow in muzzle and back skull is incorrect as are massive, cheeky heads. The jaws are powerful and free from snippiness-- the muzzle neither long and narrow nor short and stubby. Nose-- The nose should be wide and the nostrils well-developed. The nose should be black on black or yellow dogs, and brown on chocolates. Nose color fading to a lighter shade is not a fault. A thoroughly pink nose or one lacking in any pigment is a disqualification. Teeth--The teeth should be strong and regular with a scissors bite; the lower teeth just behind, but touching the inner side of the upper incisors. A level bite is acceptable, but not desirable. Undershot, overshot, or misaligned teeth are serious faults. Full dentition is preferred. Missing molars or pre-molars are serious faults. Ears--The ears should hang moderately close to the head, set rather far back, and somewhat low on the skull; slightly above eye level. Ears should not be large and heavy, but in proportion with the skull and reach to the inside of the eye when pulled forward. Eyes--Kind, friendly eyes imparting good temperament, intelligence and alertness are a hallmark of the breed. They should be of medium size, set well apart, and neither protruding nor deep set. Eye color should be brown in black and yellow Labradors, and brown or hazel in chocolates. Black, or yellow eyes give a harsh expression and are undesirable. Small eyes, set close together or round prominent eyes are not typical of the breed. Eye rims are black in black and yellow Labradors; and brown in chocolates. Eye rims without pigmentation is a disqualification.

Neck, Topline and Body
Neck--The neck should be of proper length to allow the dog to retrieve game easily. It should be muscular and free from throatiness. The neck should rise strongly from the shoulders with a moderate arch. A short, thick neck or a "ewe" neck is incorrect. Topline--The back is strong and the topline is level from the withers to the croup when standing or moving. However, the loin should show evidence of flexibility for athletic endeavor. Body--The Labrador should be short-coupled, with good spring of ribs tapering to a moderately wide chest. The Labrador should not be narrow chested; giving the appearance of hollowness between the front legs, nor should it have a wide spreading, bulldog-like front. Correct chest conformation will result in tapering between the front legs that allows unrestricted forelimb movement. Chest breadth that is either too wide or too narrow for efficient movement and stamina is incorrect. Slab-sided individuals are not typical of the breed; equally objectionable are rotund or barrel chested specimens. The underline is almost straight, with little or no tuck-up in mature animals. Loins should be short, wide and strong; extending to well developed, powerful hindquarters. When viewed from the side, the Labrador Retriever shows a well-developed, but not exaggerated forechest. Tail--The tail is a distinguishing feature of the breed. It should be very thick at the base, gradually tapering toward the tip, of medium length, and extending no longer than to the hock. The tail should be free from feathering and clothed thickly all around with the Labrador's short, dense coat, thus having that peculiar rounded appearance that has been described as the "otter" tail. The tail should follow the topline in repose or when in motion. It may be carried gaily, but should not curl over the back. Extremely short tails or long thin tails are serious faults. The tail completes the balance of the Labrador by giving it a flowing line from the top of the head to the tip of the tail. Docking or otherwise altering the length or natural carriage of the tail is a disqualification.

Forequarters
Forequarters should be muscular, well coordinated and balanced with the hindquarters. Shoulders--The shoulders are well laid-back, long and sloping, forming an angle with the upper arm of approximately 90 degrees that permits the dog to move his forelegs in an easy manner with strong forward reach. Ideally, the length of the shoulder blade should equal the length of the upper arm. Straight shoulder blades, short upper arms or heavily muscled or loaded shoulders, all restricting free movement, are incorrect. Front Legs--When viewed from the front, the legs should be straight with good strong bone. Too much bone is as undesirable as too little bone, and short legged, heavy boned individuals are not typical of the breed. Viewed from the side, the elbows should be directly under the withers, and the front legs should be perpendicular to the ground and well under the body. The elbows should be close to the ribs without looseness. Tied-in elbows or being "out at the elbows" interfere with free movement and are serious faults. Pasterns should be strong and short and should slope slightly from the perpendicular line of the leg. Feet are strong and compact, with well-arched toes and well-developed pads. Dew claws may be removed. Splayed feet, hare feet, knuckling over, or feet turning in or out are serious faults.

Hindquarters
The Labrador's hindquarters are broad, muscular and well-developed from the hip to the hock with well-turned stifles and strong short hocks. Viewed from the rear, the hind legs are straight and parallel. Viewed from the side, the angulation of the rear legs is in balance with the front. The hind legs are strongly boned, muscled with moderate angulation at the stifle, and powerful, clearly defined thighs. The stifle is strong and there is no slippage of the patellae while in motion or when standing. The hock joints are strong, well let down and do not slip or hyper-extend while in motion or when standing. Angulation of both stifle and hock joint is such as to achieve the optimal balance of drive and traction. When standing the rear toes are only slightly behind the point of the rump. Over angulation produces a sloping topline not typical of the breed. Feet are strong and compact, with well-arched toes and well-developed pads. Cow-hocks, spread hocks, sickle hocks and over-angulation are serious structural defects and are to be faulted.

Coat
The coat is a distinctive feature of the Labrador Retriever. It should be short, straight and very dense, giving a fairly hard feeling to the hand. The Labrador should have a soft, weather-resistant undercoat that provides protection from water, cold and all types of ground cover. A slight wave down the back is permissible. Woolly coats, soft silky coats, and sparse slick coats are not typical of the breed, and should be severely penalized.

Color
The Labrador Retriever coat colors are black, yellow and chocolate. Any other color or a combination of colors is a disqualification. A small white spot on the chest is permissible, but not desirable. White hairs from aging or scarring are not to be misinterpreted as brindling. Black--Blacks are all black. A black with brindle markings or a black with tan markings is a disqualification. Yellow--Yellows may range in color from fox-red to light cream, with variations in shading on the ears, back, and underparts of the dog. Chocolate--Chocolates can vary in shade from light to dark chocolate. Chocolate with brindle or tan markings is a disqualification.

Movement
Movement of the Labrador Retriever should be free and effortless. When watching a dog move toward oneself, there should be no sign of elbows out. Rather, the elbows should be held neatly to the body with the legs not too close together. Moving straight forward without pacing or weaving, the legs should form straight lines, with all parts moving in the same plane. Upon viewing the dog from the rear, one should have the impression that the hind legs move as nearly as possible in a parallel line with the front legs. The hocks should do their full share of the work, flexing well, giving the appearance of power and strength. When viewed from the side, the shoulders should move freely and effortlessly, and the foreleg should reach forward close to the ground with extension. A short, choppy movement or high knee action indicates a straight shoulder; paddling indicates long, weak pasterns; and a short, stilted rear gait indicates a straight rear assembly; all are serious faults. Movement faults interfering with performance including weaving; side-winding; crossing over; high knee action; paddling; and short, choppy movement, should be severely penalized.

Temperament
True Labrador Retriever temperament is as much a hallmark of the breed as the "otter" tail. The ideal disposition is one of a kindly, outgoing, tractable nature; eager to please and non-aggressive towards man or animal. The Labrador has much that appeals to people; his gentle ways, intelligence and adaptability make him an ideal dog. Aggressiveness towards humans or other animals, or any evidence of shyness in an adult should be severely penalized.

Disqualifications
1. Any deviation from the height prescribed in the Standard.
2. A thoroughly pink nose or one lacking in any pigment.
3. Eye rims without pigment.
4. Docking or otherwise altering the length or natural carriage of the tail.
5. Any other color or a combination of colors other than black, yellow or chocolate as described in the Standard.

Approved February 12, 1994
Effective March 31, 1994

Copy/pasted from the AKC website. http://www.akc.org/breeds/labrador_retriever/index.cfm

I wrote this article to educate the commonly mislead Labrador puppy future buyer researcher, but it can be applied to any breed.

Laura