The book 'Wood Variation: In Correlation with Planting Density and Clone' explains the variability of Rubberwood under four planting densities (500, 1000, 1500, and 2000 trees/ha)and two clones RRIM 2020 and 2025 in Malaysia. The book covers the variation in wood anatomical properties such as fiber, vessel, and ray features; wood physical properties like air-dry density, and longitudinal, radial, tangential, and volume shrinkages; and wood mechanical properties. The finding of this study would help the authorities to have a clear idea for choosing a tailored planting density from the two clones for planting in vast area.