diff --git a/src/Nito.Comparers.Core/ComparableBase.cs b/src/Nito.Comparers.Core/ComparableBase.cs
index e694feb..19770e1 100644
--- a/src/Nito.Comparers.Core/ComparableBase.cs
+++ b/src/Nito.Comparers.Core/ComparableBase.cs
@@ -36,7 +36,7 @@ public abstract class ComparableBase<T> : IEquatable<T>, IComparable, IComparabl
         /// </summary>
         /// <param name="other">The object to compare with this instance. May be <c>null</c>.</param>
         /// <returns>A value indicating whether this instance is equal to the specified object.</returns>
-        public bool Equals(T other) => ComparableImplementations.ImplementEquals(DefaultComparer, (T)this, other!);
+        public bool Equals([MaybeNull] T other) => ComparableImplementations.ImplementEquals(DefaultComparer, (T)this, other!);
 
         /// <summary>
         /// Returns a value indicating the relative order of this instance and the specified object: a negative value if this instance is less than the specified object; zero if this instance is equal to the specified object; and a positive value if this instance is greater than the specified object.
@@ -50,6 +50,6 @@ public abstract class ComparableBase<T> : IEquatable<T>, IComparable, IComparabl
         /// </summary>
         /// <param name="other">The object to compare with this instance. May be <c>null</c>.</param>
         /// <returns>A value indicating the relative order of this instance and the specified object: a negative value if this instance is less than the specified object; zero if this instance is equal to the specified object; and a positive value if this instance is greater than the specified object.</returns>
-        public int CompareTo(T other) => ComparableImplementations.ImplementCompareTo(DefaultComparer, (T)this, other!);
+        public int CompareTo([MaybeNull] T other) => ComparableImplementations.ImplementCompareTo(DefaultComparer, (T)this, other!);
     }
 }
diff --git a/src/Nito.Comparers.Core/EquatableBase.cs b/src/Nito.Comparers.Core/EquatableBase.cs
index 2372d1f..815c8f0 100644
--- a/src/Nito.Comparers.Core/EquatableBase.cs
+++ b/src/Nito.Comparers.Core/EquatableBase.cs
@@ -36,6 +36,6 @@ public abstract class EquatableBase<T> : IEquatable<T> where T : EquatableBase<T
         /// </summary>
         /// <param name="other">The object to compare with this instance. May be <c>null</c>.</param>
         /// <returns>A value indicating whether this instance is equal to the specified object.</returns>
-        public bool Equals(T other) => ComparableImplementations.ImplementEquals(DefaultComparer, (T)this, other!);
+        public bool Equals([MaybeNull] T other) => ComparableImplementations.ImplementEquals(DefaultComparer, (T)this, other!);
     }
 }
diff --git a/src/Nito.Comparers.Core/Nito.Comparers.Core.csproj b/src/Nito.Comparers.Core/Nito.Comparers.Core.csproj
index 1d23391..3132bec 100644
--- a/src/Nito.Comparers.Core/Nito.Comparers.Core.csproj
+++ b/src/Nito.Comparers.Core/Nito.Comparers.Core.csproj
@@ -5,4 +5,10 @@
     <PackageTags>comparer;equalitycomparer;icomparable;iequatable</PackageTags>
     <RootNamespace>Nito.Comparers</RootNamespace>
   </PropertyGroup>
+  <ItemGroup>
+    <PackageReference Include="Nullable" Version="1.3.0">
+      <PrivateAssets>all</PrivateAssets>
+      <IncludeAssets>runtime; build; native; contentfiles; analyzers; buildtransitive</IncludeAssets>
+    </PackageReference>
+  </ItemGroup>
 </Project>
diff --git a/src/Nito.Comparers.Core/Util/ComparableImplementations.cs b/src/Nito.Comparers.Core/Util/ComparableImplementations.cs
index 99f68e4..dc91e90 100644
--- a/src/Nito.Comparers.Core/Util/ComparableImplementations.cs
+++ b/src/Nito.Comparers.Core/Util/ComparableImplementations.cs
@@ -1,5 +1,6 @@
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 
 namespace Nito.Comparers.Util
 {
@@ -77,7 +78,7 @@ public static bool ImplementEquals(System.Collections.IEqualityComparer equality
         /// <param name="equalityComparer">The comparer. May not be <c>null</c>.</param>
         /// <param name="left">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
         /// <param name="right">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
-        public static bool ImplementOpEquality<T>(IEqualityComparer<T> equalityComparer, T left, T right)
+        public static bool ImplementOpEquality<T>(IEqualityComparer<T> equalityComparer, [MaybeNull] T left, [MaybeNull] T right)
         {
             _ = equalityComparer ?? throw new ArgumentNullException(nameof(equalityComparer));
             return equalityComparer.Equals(left, right);
@@ -90,7 +91,7 @@ public static bool ImplementOpEquality<T>(IEqualityComparer<T> equalityComparer,
         /// <param name="equalityComparer">The comparer. May not be <c>null</c>.</param>
         /// <param name="left">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
         /// <param name="right">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
-        public static bool ImplementOpInequality<T>(IEqualityComparer<T> equalityComparer, T left, T right)
+        public static bool ImplementOpInequality<T>(IEqualityComparer<T> equalityComparer, [MaybeNull] T left, [MaybeNull] T right)
         {
             _ = equalityComparer ?? throw new ArgumentNullException(nameof(equalityComparer));
             return !equalityComparer.Equals(left, right);
@@ -103,7 +104,7 @@ public static bool ImplementOpInequality<T>(IEqualityComparer<T> equalityCompare
         /// <param name="comparer">The comparer. May not be <c>null</c>.</param>
         /// <param name="left">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
         /// <param name="right">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
-        public static bool ImplementOpLessThan<T>(IComparer<T> comparer, T left, T right)
+        public static bool ImplementOpLessThan<T>(IComparer<T> comparer, [MaybeNull] T left, [MaybeNull] T right)
         {
             _ = comparer ?? throw new ArgumentNullException(nameof(comparer));
             return comparer.Compare(left, right) < 0;
@@ -116,7 +117,7 @@ public static bool ImplementOpLessThan<T>(IComparer<T> comparer, T left, T right
         /// <param name="comparer">The comparer. May not be <c>null</c>.</param>
         /// <param name="left">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
         /// <param name="right">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
-        public static bool ImplementOpGreaterThan<T>(IComparer<T> comparer, T left, T right)
+        public static bool ImplementOpGreaterThan<T>(IComparer<T> comparer, [MaybeNull] T left, [MaybeNull] T right)
         {
             _ = comparer ?? throw new ArgumentNullException(nameof(comparer));
             return comparer.Compare(left, right) > 0;
@@ -129,7 +130,7 @@ public static bool ImplementOpGreaterThan<T>(IComparer<T> comparer, T left, T ri
         /// <param name="comparer">The comparer. May not be <c>null</c>.</param>
         /// <param name="left">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
         /// <param name="right">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
-        public static bool ImplementOpLessThanOrEqual<T>(IComparer<T> comparer, T left, T right)
+        public static bool ImplementOpLessThanOrEqual<T>(IComparer<T> comparer, [MaybeNull] T left, [MaybeNull] T right)
         {
             _ = comparer ?? throw new ArgumentNullException(nameof(comparer));
             return comparer.Compare(left, right) <= 0;
@@ -142,7 +143,7 @@ public static bool ImplementOpLessThanOrEqual<T>(IComparer<T> comparer, T left,
         /// <param name="comparer">The comparer. May not be <c>null</c>.</param>
         /// <param name="left">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
         /// <param name="right">A value of type <typeparamref name="T"/> or <c>null</c>.</param>
-        public static bool ImplementOpGreaterThanOrEqual<T>(IComparer<T> comparer, T left, T right)
+        public static bool ImplementOpGreaterThanOrEqual<T>(IComparer<T> comparer, [MaybeNull] T left, [MaybeNull] T right)
         {
             _ = comparer ?? throw new ArgumentNullException(nameof(comparer));
             return comparer.Compare(left, right) >= 0;