The importance of spatial spheres in dramas has only slightly been researched. On the whole this problem has been considered relatively unimportant. Ever since the publication of Lessing’s Laokoon the distinguishing characteristic of a literary work was considered to be the element of “time”, in contradistinction to works of the visual arts (painting and sculpture) where “space” was primary. It will be demonstrated that in Barlach’s plays space assumes considerable importance. Although the dramatic concern is primarily expressed through successive dialogues and monologues, Barlach’s language nevertheless can imaginatively create spatial spheres different from those visible on stage. Both spheres of action, the visible and the invisible, are important for the function of the plot. This thesis tries to demonstrate: First, that there exists a specific dramatic problem as to spatial spheres in the plays of Ernst Barlach; Second, that the spatial spheres can be viewed as self-supporting elements contributing toward the interpretation of a given play; Third, that the interrelationship of the visible to the invisible spatial spheres and the lines of demarcation between them is of utmost importance. As representative of these two spheres in Barlach’s works, I have chosen Der blaue Boll and Der tote Tag. In Der tote Tag the relationship of the visible to the invisible leads to the problem of vision in a single-scene play. Decisive here is not the fact of the unity of place, but the perspective relative to the visible scenes in the total context of the play. In Der blaue Boll the invisible spatial spheres are realized through the stage setting; they project inner events – both visionary and real – of the individual characters. Decisive for the specific assertion of the existence of spatial spheres in a multiple-scene play is the relationship of invisible projected space images to the stage setting as well as the interaction of individual scenes to each other. A brief survey of the other six Barlach-plays shows the same development of the interrelationship of the visible to the invisible spheres; both are important for the interpretation. In the second part of the thesis the relationship of the spatial spheres to the dialogue, the characters, and to time are discussed. It is postulated that the formation of various spatial spheres can express the general ideological foundation and the specific intellectual position in a play. But beyond these assertions the conclusion is reached that the structure of spatial spheres indicates the development of the plot. Through widening, confinement, circular movement, or ascent of the various spatial structures, specific plot movements are made physically visible. Barlach strives for the synthesis of the sterilized realistic spatial sphere with an objective eternal space, between which the human soul appears to be the scene of action subjected to varying changes, yet at the same time remaining in a state of serenity. The final part deals with the specific problem of the production of Barlach’s plays. A synthesis between realism and symbolism, the empirical and the supernatural, has seldom been staged satisfactorily. Yet Barlach’s style combines both in various spatial spheres. In every one of Barlach’s plays the problem of the relationship of the visible-finite to the invisible-infinite, the obvious to the unprecedented, is characteristic. But the infinite can only be experienced by means of the finite. Only through the realistic portrayal of the finite can the invisible be made apparent.