The main objective of this book is to provide basic explanations about drawing a project-based network diagrams and to estimate the project completion duration and cost in particular. Thus, this book has been well structured to explore the bases and basics of network analyses in relation to activity time and cost. In Chapter 1, the introduction for drawing a project network is explained with the limitations and rules applied for. Chapter 2 explains the determination of activity and project based time (duration), respective probability and floating possibility; and Chapter 3 consists of critical path analyses. Considering the activity duration and cost, the book introduces three conceptualised perspectives for a project in the rest of the chapters (4, 5 and 6), respectively: Normal duration and normal cost, Minimum duration and its associated cost, and Minimum Cost and its associated duration; and this book counts the credits on the conceptualisation.