"As with all forms of story-telling that are composed in words, not in visual images, radio always leaves that magical and enigmatic margin, that space of the invisible, 'which must be filled in by the imagination of the listener "
Angela Carter preface to the collected plays, 1985.

Plays which are set mostly in one location with a lot of talk will sound dull on radio without the visual stimulus of the theatre. So a variety of sound is essential for holding the listener's attention and engaging their imagination. This can be achieved by varying the lengths of scenes, number of people speaking, pace of dialogue, volume of sound, background acoustics and locations.

For example on radio, one room sounds very like another, if they're about the same size, but the difference between an interior and an exterior acoustic is considerable. Also the contrast between a noisy sequence with a number of voices and effects and a quiet passage of interior monologue, is dramatic and effective.

The radio Dramatist can work on the principle that anything which can be described can be imagined. A radio play need not be restricted by time or place. It can travel between centuries and continents. It can take place in aeroplanes, on board ships or in exotic locations. It can also take place within the confines of a single mind. Since it is a medium of almost unlimited possibilities, it calls for great discipline of structure and an awareness of the nuances of language on the part of the writer. The writer must think in sound. It is their sole means of holding the listener's attention. Theatre, film and television can use light, colour, exciting sets and beautiful actors to hold their audience. A radio writer must combine good dialogue with the appropriate use of sound effects and music to stimulate pictures in the minds of their audience. It is important to note that good dialogue, that which is interesting and exciting, will carry a play a long way.

Along with dialogue, the other aural tools the writer has are sound effects (naturalistic or imaginary), music and silence. This last element is vital in a radio play. Pauses allow the listener time to absorb what they have just heard and prepare for what happens next. Dialogue is the dominant element of a radio play. It carries information for the listener about character, story and at times location. However, radio dialogue has to be more explicit than that written for a visual medium. So the radio writer's skill is in making this extra description sound natural. Poor dialogue in a radio play is when the characters just chat on aimlessly. The writer's skill is in choosing the precise lines needed to tell the story and bring their characters to life.