This paper describes the identification of single- and few-layer boron nitride (BN) using optical and Raman spectroscopy. BN monolayers are difficult to detect due to their low optical contrast, but can be identified by optimizing viewing conditions. Raman spectroscopy is used to confirm BN monolayers, as they exhibit an upshift in the fundamental Raman mode by up to 4 cm⁻¹. The number of layers in thicker crystals can be determined by the integer-step increase in Raman intensity and optical contrast. Few-nanometer-thick BN sheets have attracted significant interest in recent years. Although individual BN planes have been isolated and studied, interest in BN monolayers has been limited compared to graphene. This is due to the lack of suitable hBN crystals for mechanical cleavage and difficulties in isolating large BN monolayers. The situation is changing with the availability of hBN single crystals, which allow the cleavage of relatively large and thin BN samples. These crystals have been used as a thin top dielectric to gate graphene and as an inert substrate for graphene devices, improving their electronic quality. BN monolayers can be identified by their optical contrast and Raman signatures. BN monolayers show little optical contrast, even with interference enhancement using oxidized Si wafers. BN monolayers show white-light contrast of less than 1.5%, making them undetectable by the human eye. The contrast changes from positive to negative between red and blue parts of the spectrum, respectively, and goes through zero in green where eye sensitivity is maximum. Thinner SiO₂ (≈80±10 nm) offers optimum visualization conditions with contrast of ~2.5% per layer, similar to that for graphene on transparent substrates. Raman spectroscopy can be used to identify BN monolayers due to shifts in the position of the characteristic BN peak. Monolayers exhibit sample-dependent blue shifts by up to 4 cm⁻¹. This is explained by a hardening of the E₂g phonon mode due to a slightly shorter B-N bond in isolated monolayers. Bilayers show red shifts due to random strain induced during cleavage. The optical contrast increases in integer steps with the number of BN layers, allowing for the identification of mono- and few-layers. However, contamination or a thin layer of water can affect the measured contrast. Raman spectroscopy is useful for identifying monolayer BN due to an upward shift in the Raman peak position. The shift depends on local strain and is not as unambiguous as the Raman signatures for graphene. The step-like increase in Raman intensity can be used for further confirmation and counting the number of layers. The analysis and strategy for hunting for mono- and few-layer BN should facilitate further work on this interesting two-dimensional insulator.This paper describes the identification of single- and few-layer boron nitride (BN) using optical and Raman spectroscopy. BN monolayers are difficult to detect due to their low optical contrast, but can be identified by optimizing viewing conditions. Raman spectroscopy is used to confirm BN monolayers, as they exhibit an upshift in the fundamental Raman mode by up to 4 cm⁻¹. The number of layers in thicker crystals can be determined by the integer-step increase in Raman intensity and optical contrast. Few-nanometer-thick BN sheets have attracted significant interest in recent years. Although individual BN planes have been isolated and studied, interest in BN monolayers has been limited compared to graphene. This is due to the lack of suitable hBN crystals for mechanical cleavage and difficulties in isolating large BN monolayers. The situation is changing with the availability of hBN single crystals, which allow the cleavage of relatively large and thin BN samples. These crystals have been used as a thin top dielectric to gate graphene and as an inert substrate for graphene devices, improving their electronic quality. BN monolayers can be identified by their optical contrast and Raman signatures. BN monolayers show little optical contrast, even with interference enhancement using oxidized Si wafers. BN monolayers show white-light contrast of less than 1.5%, making them undetectable by the human eye. The contrast changes from positive to negative between red and blue parts of the spectrum, respectively, and goes through zero in green where eye sensitivity is maximum. Thinner SiO₂ (≈80±10 nm) offers optimum visualization conditions with contrast of ~2.5% per layer, similar to that for graphene on transparent substrates. Raman spectroscopy can be used to identify BN monolayers due to shifts in the position of the characteristic BN peak. Monolayers exhibit sample-dependent blue shifts by up to 4 cm⁻¹. This is explained by a hardening of the E₂g phonon mode due to a slightly shorter B-N bond in isolated monolayers. Bilayers show red shifts due to random strain induced during cleavage. The optical contrast increases in integer steps with the number of BN layers, allowing for the identification of mono- and few-layers. However, contamination or a thin layer of water can affect the measured contrast. Raman spectroscopy is useful for identifying monolayer BN due to an upward shift in the Raman peak position. The shift depends on local strain and is not as unambiguous as the Raman signatures for graphene. The step-like increase in Raman intensity can be used for further confirmation and counting the number of layers. The analysis and strategy for hunting for mono- and few-layer BN should facilitate further work on this interesting two-dimensional insulator.