Making a great salad is anything but a casual affair. You can't just throw some greens together with a little dressing and expect to have a salad of significance.

A mixed green salad should tingle and tantalize with its textures and colors. It should sparkle with sweet herbal flavors or surprise with its tanginess. Everything must play together in your mouth.

Never should a salad be an afterthought. And never ever should it be held in less esteem than the rest of the meal.

A great green salad should have at least five major ingredients. Normally, two would come from the mildly flavored group, perhaps romaine and bibb, and two from the strongly flavored group, say watercress and julienned belgian endive. And then there should be some accents, perhaps an avocado cut into half-inch dice, and some herbs -- a little fresh rosemary and a big handful of fresh chives. And there you have a great green salad: romaine and bibb as the base, watercress and endive for character, avocados and herbs for accents.

Lettuce Join Together

Great salads are easy to make once you understand the concept of the three groups of ingredients, and that great salads combine at least two, but more often all three. Here are the most popular and available in each category.

Mild Greens: Romaine has long, tender to slightly crisp leaves with a mild, slightly pungent flavor, and is a great all-purpose salad base. Spinach is a dark, wrinkled green leaf with a chewy texture and a mild, almost musty taste. Boston lettuce is a large, loosely furled lettuce with a soft texture and mild, sweet flavor. Bibb is a smaller lettuce much like boston, with a pale, yellowish-green color. The leaf lettuces, green and ruby, are large, flat, soft, slightly wrinkled greens with a mild, sweet flavor (slightly more flavorful than boston or bibb). Green leaf lettuce has a dull, darker green hue on the top edge of its leaves, ruby leaf lettuce has a muted burgundy blush on its leaf ends.

All of the mild greens make excellent base leaves for salads, though occasionally, when leaves from the strong category are used as the base, mild greens are used as the accent to temper the flavor and soften the texture. Bibb lettuce is extraordinarily good for this. Iceberg lettuce is crisp, watery, almost tasteless, and not much favored by lettuce lovers because of its blandness.

Strong Greens: Escarole and chicory are strong and sharp tasting. Both are long and narrow with thick spines. But escarole is basically a flat-leafed lettuce, while chicory is curled on the edges. Rocket, also called arugula, is a popular Italian leaf with a dark green color and a tart flavor. Watercress has small dark green leaves with a peppery flavor; when young they have thin stems that are edible and add a crisp texture to salads. Sorrel has shield-shaped leaves with a tart, lemony flavor. Belgian endive has tight, bullet-shaped heads with satiny white leaves trimmed with softer, yellow edges. Raddichio has small heads of burgundy leaves and is slightly bitter.

Of these, escarole (sometimes called broad or flat-leaf endive) and chicory (sometimes called curly-leafed endive) can be used as the base green for a salad, though usually they are used in a supporting role. Watercress can be used as a base or to add character. Rocket and belgian endive can be used as a base or as a secondary flavor. Sorrel is always supportive.

Accents: Certain fruits and vegetables make excellent accents to green salads. Sectioned orange or grapefruit add textural interest and acidity. Pomegranate seeds and carrots -- julienned, never grated -- add color and sweetness. Cucumbers add sweetness and a refreshing crunch. Diced avocados add a smooth, rich character. Red cabbage adds a depth of color, but its tough texture and strong flavor are not to my liking. If you put cabbage in your green salads, the milder, wrinkly napa cabbage is a good choice. Scallions and red onion rings make great accents for strongly flavored salads as well, as do capers when used discreetly.

Flowers and blossoms, when in season, can be used to add pizzazz to a salad, as well as sweetness and perfume. Among my favorites are the gold marigold leaves, the lavender blooms of chive plants with their mild onion flavor, violet leaves, which have a deep color and fine perfume that go well with soft, mild greens, and the vibrant yellow and orange leaves of nasturtiums and squash blossoms.

It is possible to find flowers and blossoms even if you don't grow your own, as they are now available in some gourmet markets. Unfortunately, many fine salad makers are intimidated by them. Don't be afraid; they're fabulous. Fresh herbs such as basil, parsley, chives and tarragon can be chopped very coarsely or shredded and just tossed into a salad. Plan half a cup for a salad that serves six people. Fresh coriander, which has a slightly more pungent flavor, is often used more sparingly. Fresh marjoram should be used discreetly (about a 1/4 to 1/3 cup for a six-serving salad). Strong herbs, such as fresh rosemary, fresh thyme or fresh oregano, also should be used sparingly -- a tablespoon or two. Chop them finely.

The light-handed use of alfalfa sprouts adds a subtle sweet nutlike flavor to salads, but too much will make the salad hay-like when it is dressed. Don't use mung bean sprouts in a salad; they belong in a wok. Nuts, which add a moment of solidity to a salad, are also an excellent accent, but tend to work best in salads that use leaves from the strong group as a base.

There are dozens of nonvegetarian gastronomic exclamation points for salads, some of which get thrown into the salad itself (like grated cheese and crisp bacon) and some of which are best blended into the dressing (like shallots and garlic).

I do not approve of tomatoes in green salads. Tomatoes have a wet, cushiony texture that adds an unwanted, unneeded, and unimaginative wet squish. Save tomatoes for tomato salads, which is where they belong.

The Stern Salad Theory

If you don't want to be bothered thinking analytically about strong and mild-flavored leaves and appropriate accents, do what my friend Margaret Stern -- perhaps the greatest green salad maker in the world -- does: she just chooses five different colored leaves, tosses them all together, and it always works. Oil (good fruity olive oil), vinegar (dark and full flavored but not too acidic), a dollop of white wine dijon mustard, and salt and pepper (freshly ground black pepper, of course) are all Stern feels are ever necessary for a dressing.

The Only Dressing

It's true. There is only one acceptable dressing for a green salad. It's the simplest dressing of all. It has unlimited possibilities. There are thousands of wonderful variations on its simple theme. There are millions of different ways to flavor it. It is the only perfect complement to a bowl of fresh garden greens. It is, of course, the classic French vinaigrette -- in its purest form, nothing more than a fine fruity olive oil with a full-bodied vinegar and a little salt and freshly ground black pepper.

It appears in the recipes that follow in just a few of its myriad forms. It can add a simple glistening sheen to your freshest garden salads, or it can be power-packed with garlic, mustard, anchovies and capers to give a piquant ring to your salad. It can be flavored with imported blue cheese for a luscious roquefort dressing, or it can be enriched with eggs for a creamy texture.

With that much versatility, there really is no need for any other dressing!

Cleaning the Leaves

All lettuces should be cored, the leaves separated and dropped into a sink filled with cold water. Watercress and other leaves that grow on stems rather than in heads should be treated the same after the stems have been cut or torn off.

Once the leaves have had a few minutes in the water, agitate them with your hands so the dirt or sand adhering to the leaves loosens. Let them rest for a few minutes so that the clean leaves float to the top and the sand falls to the bottom of the sink. Remove the leaves from the sink, a few at a time, tearing each into small pieces (the best salads are made with bite-size greens that move easily from the plate into our mouth), and drop them into a salad spinner. Spin dry.

Ahead-of-Time Setup

If you want, you can make both the salad and the dressing several hours before serving. Mix the dressing and pour it into the bottom of a large decorated salad bowl.

Drop the greens on top, without mixing, and drape the salad bowl with a dampened towel. Set aside at room temperature for up to three hours.

If you need to hold the salad for another hour or two, just dampen the towel again. To serve, toss well, being careful to get the dressing up and onto the leaves.

When To Eat Green Salad

You can eat a green salad any time you want. But I don't consider it acceptable to eat a simple green salad before a meal. Green salads should be served with the meal, as an accompaniment to a grilled cheese sandwich, for example, or after the main course, as a way to lighten the palate and seduce it into dessert. Simple green salads also can be served as part of the cheese course.

Here are two great green salads, for those of you who want recipes -- but my advice is just to go to the market, buy a mountain of wonderful green leaves, and create your own.

A REFRESHING, DEFINITIVELY GREEN SALAD

(6 servings)

This is my idea of a simple green salad. Simple because all of the flavors blend to form a refreshingly single new taste with unexpected subtleties. And green, because, obviously, everything is green -- well, sort of. The recipe calls for one of those long, plastic-wrapped, hydroponic cucumbers that are available in most supermarkets. They are less seedy and less watery, but if you wish, you can substitute two medium-size ordinary cucumbers.

2 small heads bibb lettuce

1 small head romaine

1 bunch watercress

1 small bunch parsley (preferably flat leaf)

1 small bunch scallions, gathered together and the green tops cut into thin rings (no more than 1/4-inch wide)

1 hydroponic cucumber, ends cut off, cucumber cut in half, horizontally, seeds scooped out with a spoon, and the halves cut into 1/4-inch-wide pieces

FOR THE DRESSING:

2/3 cup olive oil

1/4 cup tarragon vinegar

1 tablespoon coarse-grained mustard

2 teaspoons dried tarragon or 1/4 cup finely chopped fresh tarragon

Salt and freshly ground black pepper to taste.

Clean the lettuces and leaves as directed above. Toss with the scallions and cucumber pieces. Combine the dressing and mix well. Toss in the salad.

Variation: A salad to serve after fish: Toss half a cup of coarsely chopped fresh dill with the greens, and substitute a clove of garlic, finely chopped, for the tarragon.

A MOST COLORFUL GREEN SALAD

(6 servings)

There are more flavors, from subtle to boldly poignant, and more textures, from crisp to elegantly soft, and more colors, yellows, a dozen different greens, and the deepest of burgundies, than one would expect to find in a green salad. But they work together to make a special salad.

1 small belgian endive, cored, quartered lengthwise, then cut into pieces about 3/4-inch wide

1 head boston lettuce, flimsy outer leaves discarded

1/4 pound fresh spinach

1 large bunch arugula

1 small head radicchioSTART NOTE:cq END NOTE

1 bunch fresh coriander

The chopped leaves and tender tops of the heart of a stalk of celery

FOR THE DRESSING:

3/4 cup very fruity olive oil

3 to 4 tablespoons (depending on how acidic you want the dressing) balsamic vinegar

1 teaspoon dijon mustard

1 big heaping teaspoon coarse-grained mustard

Salt and freshly ground black pepper to taste.

Clean the lettuce and leaves as directed above. Toss with the celery. Combine dressing ingredients and mix well. Toss on the salad.