This presentation is about general features or criteria about daylighting design. Daylight as a primary light source for buildings, is a combination of direct sunlight and diffuse light emitted from sky. Daylighting defines the use of this light source (natural light) in buildings. The main concern is how to set the daylighting design issues effectively and in a comfortable way. So, the seminar initially covers the functional requirements of daylighting focusing on its dynamic character. It continues with three main items to explain why we need daylight. It is necessary to know the benefits of daylighting in detail to figure out its significance while having knowledge about its negative impacts make the designers/professionals to take precautions in the design process; or make researchers to generate and evaluate research problems. Subsequently, some basic definitions about the sun and the sky are technical information which are implemented in daylighting design simulations. To use natural light in buildings, first, it needs to be collected through some openings. Then, it is transported to the inside through glazing and daylighting systems. Final step covers the distribution of transported light effectively and evenly in the interior room. General rules of thumb and design criteria are included in this section. The presentation ends with explanations of several parameters, namely, illuminance, distribution of luminance, glare, color and directionality, to predict and test the daylight performance in buildings, together with design parameters to satisfy visual comfort conditions and to minimize the electrical energy.