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- Sight Lines
This involves two main parts - left and right; up and down. The basic principle is that the audience should be able to see everything that is happening on stage. If this is not the case, either you are avant-garde or doing it wrong. Large, opaque items should therefore go at the back of the set. chairs, stools, potted plants that aren't too tall, are often nice to have in front.
A slightly more subtle part of this is that the audience member is not all in the center. So angled set pieces can block sight lines for some audience members but not for others - Acting Spaces
Directors are really obsessed with the idea of levels. This is bound up with the idea of acting spaces. Directors will often have different parts on the stage that are supposed to represent different areas, or that different actors are supposed to use in different times. These can often be quite distinct, and perhaps the central problem of set design is to unify all of these desperate areas into one unified stage picture. Directors also like the idea of levels, so that actors can seem to be much higher than others. Places to sit are also often useful. To consider: a good height for one step is 8.5". - Entrances, Exits, and Tormentors
Another important thing to consider is where the entrances/exits are on stage. In La Sala, this is usually controlled by the setup of both the set pieces and the black curtains (also known as tormentors). You control (in conjunction with the technical director) the hanging of the blacks. They must be on pipes, but other than that can be anywhere. Also important to consider is the path from West Lounge to wherever you want the entrances to be. There are lots of options, but be aware of sight lines. The Kitchen Doors, the many entrances into La Sala, and judicious use of blacks are your friends.
Designing a set in the round
Remember that you can't have any tall pieces or lines of sight will be broken. However, small pieces can be hung from the ceiling to help create an image.
It you have a square or rectangular set, people tend to want to enter through the corners, so have those be the entrances. To be clearer, have the set look like A not B. This also avoids the issue of circular seating. 
Also keep in mind that we don't have enough blacks to have some on all four sides.
As a side note, we strongly recommend against a theater in the round:
- As an audience member, it looks cool as you enter but if your audience is only half of house, it looks very awkward and the fact that no one came is in the back of your mind during the whole performance
- It makes lighting harder (actors need to be lit from all sides)
- It's harder to fit in the space (Sala is a very narrow rectangle)
- It's harder to stage (you need to make sure that all sides of the audience get as much action)
- It's harder for actors to understand their entrances and where they are supposed to face
Before Auditions
The set designer should read the play and come with some general ideas for feel of the set and how the actors will interact with the set. They should then meet with or talk to the director about the director's concept for the set, and agree on a basic atmosphere as well as major set pieces (platforms, pillars, or other such things that will need to be blocked around).
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