In Spider Project resources are divided into two separate objects: renewable resources (people, machines) and consumable resources (materials, equipment). This way Spider Project users can define that renewable resources consume materials (a car consumes gas) during their work.

Both renewable and consumable resources may be produced (supplied) and used or consumed on project activities. Variable resource availability may be defined in time and/or through resource production and consumption on project activities.

Resources may be assigned on activities to work in teams (together), or independently (e.g. in different shifts), part time, and with variable workload (e.g. when they are not busy at activities with higher priorities).
Assigned resources may have different productivities and activity duration is calculated basing on activity volume (quantity) of work and total productivity of assigned resources.

Spider Project users can create predefined crews (multi-resources) and assign crews thus assigning all resources that belong to these crews. At any moment the crews may be changed and these changes will be applied to all future crew assignments. This option is very useful for what if evaluations and resource management during project execution.
Project and Portfolio schedules may be calculated taking into account supply restrictions and delaying activities if materials necessary for their completion are not available.