diff --git a/halo2_proofs/src/helpers.rs b/halo2_proofs/src/helpers.rs
index 2158a369..e56758fb 100644
--- a/halo2_proofs/src/helpers.rs
+++ b/halo2_proofs/src/helpers.rs
@@ -14,3 +14,22 @@ pub(crate) trait CurveRead: CurveAffine {
 }
 
 impl<C: CurveAffine> CurveRead for C {}
+
+/// Converts a slice of `bool` into a `u8`.
+///
+/// Panics if the slice has length greater than 8.
+pub fn pack(bits: &[bool]) -> u8 {
+    let mut value = 0u8;
+    assert!(bits.len() <= 8);
+    for (bit_index, bit) in bits.iter().enumerate() {
+        value |= (*bit as u8) << bit_index;
+    }
+    value
+}
+
+/// Writes the first `bits.len()` bits of a `u8` into `bits`.
+pub fn unpack(byte: u8, bits: &mut [bool]) {
+    for (bit_index, bit) in bits.iter_mut().enumerate() {
+        *bit = (byte >> bit_index) & 1 == 1;
+    }
+}
diff --git a/halo2_proofs/src/plonk.rs b/halo2_proofs/src/plonk.rs
index e96cf3fe..3557517a 100644
--- a/halo2_proofs/src/plonk.rs
+++ b/halo2_proofs/src/plonk.rs
@@ -9,9 +9,10 @@ use blake2b_simd::Params as Blake2bParams;
 use group::ff::{Field, FromUniformBytes, PrimeField};
 
 use crate::arithmetic::CurveAffine;
+use crate::helpers::{pack, unpack, CurveRead};
 use crate::poly::{
-    Coeff, EvaluationDomain, ExtendedLagrangeCoeff, LagrangeCoeff, PinnedEvaluationDomain,
-    Polynomial,
+    commitment::Params, Coeff, EvaluationDomain, ExtendedLagrangeCoeff, LagrangeCoeff,
+    PinnedEvaluationDomain, Polynomial,
 };
 use crate::transcript::{ChallengeScalar, EncodedChallenge, Transcript};
 
@@ -47,17 +48,131 @@ pub struct VerifyingKey<C: CurveAffine> {
     cs_degree: usize,
     /// The representative of this `VerifyingKey` in transcripts.
     transcript_repr: C::Scalar,
+    selectors: Vec<Vec<bool>>,
 }
 
 impl<C: CurveAffine> VerifyingKey<C>
 where
     C::Scalar: FromUniformBytes<64>,
 {
+    /// Writes a verifying key to a buffer.
+    pub fn write<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
+        // Version byte that will be checked on read.
+        writer.write_all(&[0x01])?;
+
+        writer.write_all(&(u32::try_from(self.fixed_commitments.len()).unwrap()).to_le_bytes())?;
+        for commitment in &self.fixed_commitments {
+            writer.write_all(commitment.to_bytes().as_ref())?;
+        }
+        self.permutation.write(writer)?;
+
+        // write self.selectors
+        writer.write_all(&(u32::try_from(self.selectors.len()).unwrap()).to_le_bytes())?;
+        for selector in &self.selectors {
+            // since `selector` is filled with `bool`, we pack them 8 at a time into bytes and then write
+            for bits in selector.chunks(8) {
+                writer.write_all(&[pack(bits)])?;
+            }
+        }
+
+        Ok(())
+    }
+
+    /// Reads a verifying key from a buffer.
+    pub fn read<R: io::Read, ConcreteCircuit: Circuit<C::Scalar>>(
+        reader: &mut R,
+        params: &Params<C>,
+    ) -> io::Result<Self> {
+        let (domain, cs, _) = keygen::create_domain::<C, ConcreteCircuit>(params);
+
+        let mut version_byte = [0u8; 1];
+        reader.read_exact(&mut version_byte)?;
+        if 0x01 != version_byte[0] {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                "unexpected version byte",
+            ));
+        }
+
+        let mut num_fixed_columns_le_bytes = [0u8; 4];
+        reader.read_exact(&mut num_fixed_columns_le_bytes)?;
+        let num_fixed_columns = u32::from_le_bytes(num_fixed_columns_le_bytes);
+
+        let fixed_commitments: Vec<_> = (0..num_fixed_columns)
+            .map(|_| C::read(reader))
+            .collect::<io::Result<_>>()?;
+
+        let permutation = permutation::VerifyingKey::read(reader, &cs.permutation)?;
+
+        // read selectors
+        let mut num_selectors_le_bytes = [0u8; 4];
+        reader.read_exact(&mut num_selectors_le_bytes)?;
+        let num_selectors = u32::from_le_bytes(num_selectors_le_bytes);
+        if cs.num_selectors != num_selectors.try_into().unwrap() {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                "unexpected number of selectors",
+            ));
+        }
+        let selectors: Vec<Vec<bool>> = vec![vec![false; params.n as usize]; cs.num_selectors]
+            .into_iter()
+            .map(|mut selector| {
+                let mut selector_bytes = vec![0u8; (selector.len() + 7) / 8];
+                reader.read_exact(&mut selector_bytes)?;
+                for (bits, byte) in selector.chunks_mut(8).zip(selector_bytes) {
+                    unpack(byte, bits);
+                }
+                Ok(selector)
+            })
+            .collect::<io::Result<_>>()?;
+
+        let (cs, _) = cs.compress_selectors(selectors.clone());
+
+        Ok(Self::from_parts(
+            domain,
+            fixed_commitments,
+            permutation,
+            cs,
+            selectors,
+        ))
+    }
+
+    /// Writes a verifying key to a vector of bytes.
+    pub fn to_bytes(&self) -> Vec<u8> {
+        let mut bytes = Vec::<u8>::with_capacity(self.bytes_length());
+        self.write(&mut bytes)
+            .expect("Writing to vector should not fail");
+        bytes
+    }
+
+    /// Reads a verifying key from a slice of bytes.
+    pub fn from_bytes<ConcreteCircuit: Circuit<C::Scalar>>(
+        mut bytes: &[u8],
+        params: &Params<C>,
+    ) -> io::Result<Self> {
+        Self::read::<_, ConcreteCircuit>(&mut bytes, params)
+    }
+
+    /// Gets the total number of bytes in the serialization of `self`.
+    fn bytes_length(&self) -> usize {
+        1 + 4
+            + self.fixed_commitments.len() * C::default().to_bytes().as_ref().len()
+            + self.permutation.bytes_length()
+            + 4
+            + self.selectors.len()
+                * self
+                    .selectors
+                    .get(0)
+                    .map(|selector| (selector.len() + 7) / 8)
+                    .unwrap_or(0)
+    }
+
     fn from_parts(
         domain: EvaluationDomain<C::Scalar>,
         fixed_commitments: Vec<C>,
         permutation: permutation::VerifyingKey<C>,
         cs: ConstraintSystem<C::Scalar>,
+        selectors: Vec<Vec<bool>>,
     ) -> Self {
         // Compute cached values.
         let cs_degree = cs.degree();
@@ -70,6 +185,7 @@ where
             cs_degree,
             // Temporary, this is not pinned.
             transcript_repr: C::Scalar::ZERO,
+            selectors,
         };
 
         let mut hasher = Blake2bParams::new()
diff --git a/halo2_proofs/src/plonk/keygen.rs b/halo2_proofs/src/plonk/keygen.rs
index bb26d5a6..1b2be6d0 100644
--- a/halo2_proofs/src/plonk/keygen.rs
+++ b/halo2_proofs/src/plonk/keygen.rs
@@ -219,7 +219,7 @@ where
     )?;
 
     let mut fixed = batch_invert_assigned(assembly.fixed);
-    let (cs, selector_polys) = cs.compress_selectors(assembly.selectors);
+    let (cs, selector_polys) = cs.compress_selectors(assembly.selectors.clone());
     fixed.extend(
         selector_polys
             .into_iter()
@@ -240,6 +240,7 @@ where
         fixed_commitments,
         permutation_vk,
         cs,
+        assembly.selectors,
     ))
 }
 
diff --git a/halo2_proofs/src/plonk/permutation.rs b/halo2_proofs/src/plonk/permutation.rs
index c81de276..2f001715 100644
--- a/halo2_proofs/src/plonk/permutation.rs
+++ b/halo2_proofs/src/plonk/permutation.rs
@@ -8,6 +8,9 @@ pub(crate) mod keygen;
 pub(crate) mod prover;
 pub(crate) mod verifier;
 
+use crate::helpers::CurveRead;
+use std::io;
+
 /// A permutation argument.
 #[derive(Debug, Clone)]
 pub(crate) struct Argument {
@@ -75,6 +78,37 @@ pub(crate) struct VerifyingKey<C: CurveAffine> {
     commitments: Vec<C>,
 }
 
+impl<C: CurveAffine> VerifyingKey<C> {
+    pub(crate) fn write<W: io::Write>(&self, writer: &mut W) -> io::Result<()> {
+        writer.write_all(&(u32::try_from(self.commitments.len()).unwrap()).to_le_bytes())?;
+        for commitment in &self.commitments {
+            writer.write_all(commitment.to_bytes().as_ref())?;
+        }
+
+        Ok(())
+    }
+
+    pub(crate) fn read<R: io::Read>(reader: &mut R, argument: &Argument) -> io::Result<Self> {
+        let mut num_commitments_le_bytes = [0u8; 4];
+        reader.read_exact(&mut num_commitments_le_bytes)?;
+        let num_commitments = u32::from_le_bytes(num_commitments_le_bytes);
+        if argument.columns.len() != num_commitments.try_into().unwrap() {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                "unexpected number of column commitments",
+            ));
+        }
+        let commitments: Vec<_> = (0..argument.columns.len())
+            .map(|_| C::read(reader))
+            .collect::<io::Result<_>>()?;
+        Ok(VerifyingKey { commitments })
+    }
+
+    pub(crate) fn bytes_length(&self) -> usize {
+        4 + self.commitments.len() * C::default().to_bytes().as_ref().len()
+    }
+}
+
 /// The proving key for a single permutation argument.
 #[derive(Clone, Debug)]
 pub(crate) struct ProvingKey<C: CurveAffine> {