Herrmann's sense of orchestration was so strong that he would use many contemporary and very specific performance techniques when composing, extending the orchestral sounds beyond the somewhat limited palette of many film composers. With the exception of the overture and the other "action" music in the film, the strings are usually muted, resulting in a darker, softer tone quality. In "The Stone Faces" when Roger and Eve first see the top of the monument when they are running from Van Damm, the violins repeat the same note, but are instructed to play poco a poco con sordino, which means that members of the string section would put their mutes on one-by-one while the others continue playing.26 This creates the unique sound of the section becoming slowly muted rather than the immediate change from senza sordino to con sordino.
Additional techniques include repeated use of pizzicato strings and the glissando. In "Kidnapped," half the strings are playing the same line pizzicato while the other half plays arco (with the bow). The glissando is used in the overture, when the violins have a grating response to the trumpet/xylophone melody as follows:

Ex. 1, Violin Glissando from North by Northwest Overture by Bernard Herrmann. Note that the violins are playing the very dissonant melodic interval of a major seventh. Combining this with the glissando creates a very eerie, piercing sound (foreshadowing the composer's later music for the famous shower sequence in Psycho). The glissando is also used extensively with the harps, which is another sound the composer liked. In the overture, the two harps are frequently playing glissandi in opposite directions at the same time.

Herrmann also avoids the traditional use of vibrato in strings, instructing players to play non vibrato unless otherwise noted, the reverse of the usual practice, and frequently instructing the performers to play sul ponticello, with the bow near the bridge, which increases the high harmonics and creates a drier, more gritty sound. In "The Airplane" as Eve is about to board the plane with Van Damm, the violins play the same figure repeatedly, but in a rapid succession of sul tasto ("with taste," or near the fingerboard, the opposite of ponticello), sul ponticello, and sul naturale (in between, or "natural"). Herrmann also avoids the use of tremolo in the strings, another technique that had become a clichˇ in suspense films.
Although the brass section is fairly standard, Herrmann emphasizes the horns, which are the darkest instruments in the section (so dark that they are traditionally considered part of the woodwinds) and relies heavily on mutes. Again, Herrmann uses contemporary orchestrational techniques normally shunned by Hollywood composers. In "Kidnapped," the cue that accompanies Roger Thornhill as he is abducted and taken to Townsend's (Van Damm's) house, two horns are instructed to play muted and two are to play stopped (with the player's hand placed fully into the bell). This results in a unique tone color which Herrmann preferred.
In "The Shooting," when Roger is "shot" at the cafeteria, the trumpets and trombones use cup mutes, the darkest of the brass mutes (generally used in jazz) for the darkest moment in the film when we believe that the hero may have been shot by his lover. The brass instruments also use straight mutes, and in "The Station" when Roger has stolen a redcap's uniform, the trumpets use Harmon mutes (a "bright" sound for a lighter comic moment when we see the real redcap in his underwear), again used primarily in jazz, but adopted by Herrmann as another orchestral color.
Unlike the other orchestral sections, the percussion section is expanded for this score. This is somewhat unusual for Herrmann, but it is linked to the narrative for several reasons. First, the climactic scene of the film takes place on the impressive structure of Mount Rushmore. The battery of percussion, particularly the timpani and cymbals, reflects the grandiose nature of the scene. Since Herrmann chose to use the South American "fandango" rhythm in the overture, the use of castanets and tambourine is logical, since these instruments are associated with the fandango. The vibraphone has always been a favorite instrument for Herrmann, and is the darkest of the pitched sounds in the percussion section.27 The timpani and bass drum are also very dark-sounding instruments. Also, since the motivic development is primarily rhythmic in the overture and final sequence, it makes sense to augment the percussion section. Finally, percussion is often associated with the military (and government functions). Herrmann may have intended a subconscious association with the government, since it is the United States government that would have allowed Roger to be killed rather than interrupt their plans.
Rhythm is unusually important in Herrmann's scores. Psycho opens with a distinctive rhythm that drives the first half of the film. For the North by Northwest score, Herrmann chose the characteristic fandango rhythm as a foundation. This rhythm is based on the hemiola, a compound rhythm of three against two (or two against three) and is normally notated as alternating measures of 6/8 time and 3/4 time. (Leonard Bernstein used the same rhythm in "America" in the musical West Side Story.) Exactly why Herrmann chose the fandango is not clear, although he appears to have been intrigued by the motion of the rhythm 28 and did not link it to the narrative of the film. Royal S. Brown thinks that it may be a carryover from Vertigo, which used a haba–era rhythm for the Mexican character of Carlotta. Perhaps there is some truth to this, since the films do have some structural similarities. Most evidently, the characters of Carlotta/Madelaine/Judy and Eve are similar. In any event, the rhythm is compositionally intriguing. Herrmann notates it in 3/8 as follows:

Ex. 2, Fandango Rhythm from North by Northwest Overture by Bernard Herrmann.

The first two measures above are clearly in three, but measures three and four have three notes divided over the two measures, creating a hemiola. Herrmann uses this rhythmic motif (and the hemiola) as his compositional cell for the rhythmic action in the score. The overture is a tour-de-force of this rhythmic development, using virtually every combination and permutation of hemiola imaginable. In addition, much of the rhythmic development is done through syncopation, in which accented notes are placed on upbeats. Compare measures three and four of this example with measures seven and eight.

Ex. 3, Melodic Syncopation in North by Northwest Overture by Bernard Herrmann. Even more noticeable is the syncopation in this quote from the overture:

Ex. 4, Sectional Syncopation in North by Northwest Overture by Bernard Herrmann.

A final example shows the hemiola again in the timpani, this time with a different melodic motif. Note that the two eighth notes across the bar line can be seen as one unit, forming three quarter notes against two measures.

Ex. 5, Hemiola/Syncopation in North by Northwest Overture by Bernard Herrmann.

Interestingly, the "love theme" introduced later in the film uses a rhythm based on the opening timpani motif (from Example 2). The quarter note followed by two eighth notes can be seen (with the meter doubled) as an abbreviation of the 3/8 pattern of an eighth note followed by four sixteenth notes.

Ex. 6, Rhythm in "Interlude" from North by Northwest by Bernard Herrmann. The "journey motif," described by Royal S. Brown, can be seen as the overture's rhythmic motif of four sixteenth notes, but without the eighth note preceding: Ź

Ex. 7, "Journey Motif" Rhythm in "The Auction" from North by Northwest by Bernard Herrmann.

This motif is used in "The Station," "The Pad and Pencil," (which follows Roger into the auction), "The Auction," "The Police" and "The Airport." In all instances, Roger is attempting to go somewhere, hence the term "journey motif." The constant motion of sixteenth notes propels Roger from one scene to the next. Another device which Herrmann uses is the dynamic build. This simply means increasing volume, either by instructing the players to crescendo or by increasing orchestration or both. Although all composers traditionally use this technique, some will write music at one dynamic level so that it remains in the background and does not become obtrusive. Herrmann uses dynamic builds in his music more than other film composers and to a much greater degree. The overture, for example, begins with the timpani almost inaudible under the roar of "Leo the Lion." It builds slowly to a frenzied pace and a full dynamic level by the end of the title sequence. Much of the "suspense" music in the film is at very low levels and orchestrated for only a few instruments, creating a tense atmosphere. "The Shooting," for instance, begins with a loud chord behind the gunshots, but when Roger's body is loaded into the ambulance, we hear solo horn and trumpet.
Besides his strong senses of orchestration and rhythm, Herrmann had unique ideas about the use of harmony. Again, Herrmann's peers would be composers such as Stravinsky, Hindemith and Copland rather than other film composers. As Royal S. Brown has stated, Herrmann bases his harmony loosely on traditional Western harmony, but then transforms the fundamental ideas enough to create an uncomfortable feeling in the listener. Although the "Hitchcock chord"29 (a minor triad with an added major seventh) is not used in North by Northwest (as it was extensively in Vertigo, Psycho and other Herrmann/Hitchcock films), the harmonic practices indicate Herrmann's autograph.
One technique Herrmann preferred was the extended use of chromaticism without standard resolution. The overture, for example, is almost continually chromatic. The opening motif in the timpani establishes chromatic movement from A to B flat. The most striking example of chromaticism occurs in the bridging section where the trumpets and xylophone play a melodic line against the bass and bassoon. The triadic harmony in the bass/bassoon line changes every two measures, shifting through eight different keys. (See the lower clef of Example 9, below.)
Another example of chromatic movement can be seen in this melodic line used in "Kidnapped." (The line continues chromatically.)

Ex. 8, Chromaticism in the "Van Damm" motif as seen in "Kidnapped" from North by Northwest by Bernard Herrmann.

Interestingly, this line is used as a suspense motif whenever Roger is about to meet Van Damm (or is seeking him).30 Technically speaking, it is not truly a "Van Damm" motif, since it usually is used only in anticipation of the character. In reality, the theme is introduced over the dissolve to the sign that has "Townsend" written on it. Whenever he appears, the music disappears, except in his final scene when he attempts to leave with Eve. Interestingly, Eve is thinking about Roger this last time the theme is stated, which helps tie the Roger and Van Damm's characters together.
Another harmonic technique Herrmann used was bitonality, composing in two different keys at the same time. Although a common practice in contemporary music, "classical" Hollywood film scores almost never used bitonality because of the resulting extreme dissonance. In the overture, the trumpets are harmonized in completely different keys from the bassoon/bass line explained above. The resulting harmonic structures are as follows:

Ex. 9, Bitonal Harmonic Motion in Bridge Section of North by Northwest Overture by Bernard Herrmann.

The effects are extremely dissonant in all cases. Another example of bitonality is a different quote from Vertigo that Herrmann uses twice. In the final sequence of North by Northwest, Herrmann quotes the music in Vertigo that accompanies the dolly/zoom shot of Jimmy Stewart's point of view as he looks down the stairs. We hear it in North by Northwest when we see the high angle shot looking down the mountain at Eve hanging to the ledge, and again as Leonard falls after he is shot. The structure is a D major triad over an E flat minor triad, as follows.

Ex. 10, Bitonal Structure from Vertigo as seen in

"The Cliff" from North by Northwest by Bernard Herrmann. Herrmann also uses the pedal point and ostinato as techniques to achieve tension. (A pedal point is one note that is held or repeated for an extended time, often in the bass. An ostinato is a short figure that is repeated frequently, also often in the bass. The results are often quite dissonant.) "The Phone Booth" uses the timpani playing a pedal B flat to create a sense of impending doom as Eve arranges Roger's death. "The Question" also uses a pedal to create tension, since this is the first time Roger has outwardly confronted her about the way she has acted, accusing her of being a murderer. The final sequences of the film use it extensively. "The House," "The Match Box," "The Message," "The Gates," and "The Cliff" all use pedals to help create tension.

26 One of the few uses of this technique is in Ravel's Daphnis et Chloˇ.
27 Herrmann also used the vibraphone extensively in his Twilight Zone scores.
28 Album liner notes.
29 As referred to by Brown.
30 In addition to "Kidnapped," the motif is used in "The Return," when Roger brings the police to search for Townsend (actually Van Damm), in "The U.N." and "Information Desk," when Roger goes to the U.N. to find Van Damm (actually Townsend), in "The Cafeteria," when Roger has arranged to meet Van Damm at Mount Rushmore, in "The House," when Roger stalks Van Damm's house at Mount Rushmore, and "The Airplane," as Eve starts to leave with Van Damm.