The ability to successfully combine typefaces is clearly a valuable design skill. But with over 100,000 fonts to choose from, the task can seem daunting. The good news is that there are four basic rules for combining different typeface designs. Follow these and you are well on your way to successful typographic mixology.

The basic rules for combining different typefaces are:

1. The family comes first
2. Embrace diversity
3. Combine similar proportions
4. Limit combinations

1. The family comes first
The safest and easiest way to take advantage of multiple typeface designs is to rely on a single, large type family for your choices. The various weights and proportions within the family provide a range of versatility. Since all the designs are from the same family, you are also guaranteed that there will be no stylistic clashes. Even the simplest type family of roman, italic and bold can provide reasonable type mixing capabilities.

For most projects, however, a large family of several weights-each with italic counterparts-will provide more flexibility. Larger type families provide more latitude of choice. So if one weight is not quite right, you'll probably be able to find one that is. Some type families also have condensed designs that can be put to good use in headlines and subheads or where space is at a premium.

There are also typeface families-sometimes called "super families"-that are made up of different subfamilies. ITC Stone is a good example. The subgroups of the Stone family consist of Serif, Sans, Humanistic and Informal. Each subfamily has roman and italic versions in three weights. The four subfamilies share the same cap heights, lowercase x-heights, stem weights and general proportions. Each typeface is designed to stand on its own as a useful communication tool. This guarantees typographic variety when the designs are used together. Thesis, Mentor, Compatil and ITC Legacy are other examples of the many super typeface families that are currently available.

2. Embrace diversity
While working "in-family" is good, using very different typeface designs is usually better. Combining distinctively different typeface designs can create a more obvious hierarchy and generate higher levels of visual interest. The typographic "Golden Rule" for combining fonts from unrelated families is simple: the more dissimilar the type designs, the better the mix. Counterpoint is a stronger typographic tool and easier to use than harmony.

The least risky "out of family" contrast is combining a serif with a sans serif typeface. Select virtually any sans serif design, combine it with just about any serif font and you're just one step over the line from absolute conservatism. Combine Avenir with Bembo, Slate with Dante or Franklin Gothic with Cartier Book, and you almost can't go wrong. One thing to keep in mind: A little diversity helps here also. Serif and sans serif typefaces that have similar design roots like Goudy Sans and Tiepolo, which are both based on calligraphic forms, can be combined, but the result may not be as successful as two designs with strong visual contrasts.

If you want to use two serif designs instead of a serif and a sans, it's best to choose very differentappearing typefaces. Try an old style type like ITC Weidemann with a modern face like Bodoni or ITC Fenice, or combine a transitional like Baskerville with a glyphic like Friz Quadrata.

Sometimes two serif faces from similar stylistic categories can be combined if the design and/or weight differences between them are markedly dissimilar- for example, the delicate stroke weight and stately proportions of ITC Berkeley Oldstyle will provide a strong counterpoint to the lively and slightly chubby Tyke.

With the variety of typefaces available, there are hundreds-probably thousands-of potentially good combinations. Combining just sans serif designs, however, becomes more challenging. The problem with combining two sans serif typefaces is that most are similar in design-especially to average readers. Strong typographic contrasts typically don't create problems, but when typefaces from different families that are similar in design are combined, design imbalance is often the result. The casual reader may not even notice that the typefaces are different, but will probably be aware of a subtle, discordant undertone within the design (think navy socks paired with black shoes).

If you think you must use two sans serif typefaces, keep in mind that only vastly different styles and weights from these families should be combined on a page. A 19th-century sans serif such as Franklin Gothic might work with a geometric sans serif like Avenir because the two are stylistically different from each other. Sans serifs that are similar in design almost never work in harmony.

3. Combine similar proportions
If you are combining different typefaces, especially in text copy, they should have similar proportions. Their respective lowercase x-heights should be close to the same size, ascenders and descenders ought to be about the same length and the general width of the characters should be similar. For the same reason that tempo should not change arbitrarily in music, combining markedly different typefaces in text copy is generally not a good idea. Combining text typefaces with dissimilar proportions can disrupt the rhythm-or typographic color-of the copy.

Typographic color can have as much impact on the readability of a block of text copy as the choice of typeface or the size it is set. Typefaces of markedly different proportions in the same copy block can make line spacing appear uneven and the text copy mottled. A page of copy that is uneven in color is distracting to the reader and can even disrupt the horizontal motion across the page. A column of text set in Truesdell, for example, is normally easy to peruse. Readers may notice the face because it is relatively distinctive, but this should not get in the way of the reading process. Truesdell sets with even typographic color. Introduce emphasis or clarification in the form of a typeface like Neo Sans or Leawood and the copy block becomes a distracting combination of typographic shapes and weights. At best, the column looks cluttered; at worst, it becomes difficult to read.

4. Limit combinations
Don't use a typeface if you don't need to. There is a thin line between typographic variety and font clutter. Where one typestyle is rarely enough, four is almost always too many. Have a reason other than "because I can" when using more than two or three different typestyles. Each typeface should provide a definite and specific purpose within the context of the piece you are designing. Used sparingly, different typefaces can provide emphasis and guidance to the reader. Think of the different typefaces as graphic road signs; just a few, well placed, will help the reader navigate through the content. Too many can create distractions and confusion.

Four rules for limitless choices
With the seemingly limitless fonts that can be purchased online, availability of choices for combining typefaces is not a problem. Selecting from all those faces, however, can be. Following the aforementioned four simple rules will go a long way toward producing successful combinations.

SIDEBAR: Use the Display Version
Type set larger than 14 point is usually considered to be at a "display" size and type set smaller than 14 point is generally defined as "text" copy. With current technology, however, any typeface can be set at virtually any size. The problem is that typefaces developed to be read as continuous text do not generally make the best display faces.

A problem with many serif typeface designs is that they do not enlarge very well. Most were drawn to work within a relatively narrow band of sizes. When they are enlarged, shapes that appear subtle at 12 point can begin to look ungainly at 72 point, and stroke weights that are hairlines at small sizes may become downright chunky at 48 point and above. The result is that a svelte, sprightly wood nymph of a typestyle at 12 point begins to take on the proportions of a linebacker when set at 72 point.

Some traditional and new text families do have special weights that have been drawn to work exceptionally well at large sizes. If you want to combine serif typefaces, consider using one of these special designs for the big type. They have been drawn with shapes and proportions that perform best at large sizes. Big Caslon, Throhand Pen and ITC Bodoni Seventy-Two are just three of many examples of fonts developed specifically for setting at large sizes.

SIDEBAR: Don't Combine Electronic Distortions
With current type imaging technology it is easy to slant and embolden letterforms. Resist the temptation. The end result will almost always look bad. When italic types are designed properly, character proportions and shifts in stroke weight are adjusted to be optically pleasing and to ensure ease of reading. The same holds true for bold designs. More weight is added to the horizontal axis than the vertical to maintain a proportional relationship with he lighter weights and enable the eye to travel smoothly across the page. Electronically distorted type ruins character stroke weights and plays havoc with sensitive character proportions. The result will almost always be unattractive and at times even illegible typography. Always use "drawn" designs when combining typefaces.

About the author
Allan Haley is the director of Words & Letters at Monotype Imaging. He is chairperson of AIGA Typography and a past president of the New York Type Directors Club.

This article was originally published in the February/March 2007 issue of Dynamic Graphics magazine

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