diff --git a/CHANGELOG.md b/CHANGELOG.md
index 3c090978c366..ea883ce028d6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -23,6 +23,9 @@ CHANGELOG
 - Automatic plugin acquisition for Go
   [#4297](https://github.com/pulumi/pulumi/pull/4297)
 
+- Add overloads to Output.All in .NET
+  [#4321](https://github.com/pulumi/pulumi/pull/4321)
+
 ## 1.14.0 (2020-04-01)
 - Fix error related to side-by-side versions of `@pulumi/pulumi`.
   [#4235](https://github.com/pulumi/pulumi/pull/4235)
diff --git a/sdk/dotnet/Pulumi.Tests/Core/OutputTests.cs b/sdk/dotnet/Pulumi.Tests/Core/OutputTests.cs
index 2949e573047c..082a50f3ebf0 100644
--- a/sdk/dotnet/Pulumi.Tests/Core/OutputTests.cs
+++ b/sdk/dotnet/Pulumi.Tests/Core/OutputTests.cs
@@ -1,6 +1,7 @@
 // Copyright 2016-2019, Pulumi Corporation
 
 using System.Collections.Immutable;
+using System.Linq;
 using System.Threading.Tasks;
 using Pulumi.Serialization;
 using Xunit;
@@ -246,6 +247,52 @@ public Task ApplyDoesNotPropagateSecretOnUnknownUnknownOutput()
                     Assert.False(data.IsSecret);
                     Assert.Null(data.Value);
                 });
+            
+            [Fact]
+            public Task AllParamsOutputs()
+                => RunInPreview(async () =>
+                {
+                    var o1 = CreateOutput(1, isKnown: true);
+                    var o2 = CreateOutput(2, isKnown: true);
+                    var o3 = Output.All(o1, o2);
+                    var data = await o3.DataTask.ConfigureAwait(false);
+                    Assert.Equal(new[] { 1, 2 }, data.Value);
+                });
+            
+            [Fact]
+            public Task AllEnumerableOutputs()
+                => RunInPreview(async () =>
+                {
+                    var o1 = CreateOutput(1, isKnown: true);
+                    var o2 = CreateOutput(2, isKnown: true);
+                    var outputs = new[] {o1, o2}.AsEnumerable();
+                    var o3 = Output.All(outputs);
+                    var data = await o3.DataTask.ConfigureAwait(false);
+                    Assert.Equal(new[] { 1, 2 }, data.Value);
+                });
+
+            [Fact]
+            public Task AllParamsInputs()
+                => RunInPreview(async () =>
+                {
+                    var i1 = (Input<int>)CreateOutput(1, isKnown: true);
+                    var i2 = (Input<int>)CreateOutput(2, isKnown: true);
+                    var o = Output.All(i1, i2);
+                    var data = await o.DataTask.ConfigureAwait(false);
+                    Assert.Equal(new[] { 1, 2 }, data.Value);
+                });
+            
+            [Fact]
+            public Task AllEnumerableInputs()
+                => RunInPreview(async () =>
+                {
+                    var i1 = (Input<int>)CreateOutput(1, isKnown: true);
+                    var i2 = (Input<int>)CreateOutput(2, isKnown: true);
+                    var inputs = new[] {i1, i2}.AsEnumerable();
+                    var o = Output.All(inputs);
+                    var data = await o.DataTask.ConfigureAwait(false);
+                    Assert.Equal(new[] { 1, 2 }, data.Value);
+                });
         }
 
         public class NormalTests
diff --git a/sdk/dotnet/Pulumi/Core/Output.cs b/sdk/dotnet/Pulumi/Core/Output.cs
index 7a29876e12cd..3e5eb53936c4 100644
--- a/sdk/dotnet/Pulumi/Core/Output.cs
+++ b/sdk/dotnet/Pulumi/Core/Output.cs
@@ -28,20 +28,36 @@ public static Output<T> CreateSecret<T>(Task<T> value)
             => Output<T>.CreateSecret(value);
 
         /// <summary>
-        /// Combines all the <see cref="Input{T}"/> values in <paramref name="inputs"/> and combines
-        /// them all into a single <see cref="Output{T}"/> with an <see cref="ImmutableArray{T}"/>
+        /// Combines all the <see cref="Input{T}"/> values in <paramref name="inputs"/>
+        /// into a single <see cref="Output{T}"/> with an <see cref="ImmutableArray{T}"/>
         /// containing all their underlying values.  If any of the <see cref="Input{T}"/>s are not
         /// known, the final result will be not known.  Similarly, if any of the <see
         /// cref="Input{T}"/>s are secrets, then the final result will be a secret.
         /// </summary>
         public static Output<ImmutableArray<T>> All<T>(params Input<T>[] inputs)
-            => All(ImmutableArray.CreateRange(inputs));
+            => Output<T>.All(ImmutableArray.CreateRange(inputs));
 
         /// <summary>
         /// <see cref="All{T}(Input{T}[])"/> for more details.
         /// </summary>
-        public static Output<ImmutableArray<T>> All<T>(ImmutableArray<Input<T>> inputs)
-            => Output<T>.All(inputs);
+        public static Output<ImmutableArray<T>> All<T>(IEnumerable<Input<T>> inputs)
+            => Output<T>.All(ImmutableArray.CreateRange(inputs));
+        
+        /// <summary>
+        /// Combines all the <see cref="Output{T}"/> values in <paramref name="outputs"/>
+        /// into a single <see cref="Output{T}"/> with an <see cref="ImmutableArray{T}"/>
+        /// containing all their underlying values.  If any of the <see cref="Output{T}"/>s are not
+        /// known, the final result will be not known.  Similarly, if any of the <see
+        /// cref="Output{T}"/>s are secrets, then the final result will be a secret.
+        /// </summary>
+        public static Output<ImmutableArray<T>> All<T>(params Output<T>[] outputs)
+            => All(outputs.AsEnumerable());
+
+        /// <summary>
+        /// <see cref="All{T}(Output{T}[])"/> for more details.
+        /// </summary>
+        public static Output<ImmutableArray<T>> All<T>(IEnumerable<Output<T>> outputs)
+            => Output<T>.All(ImmutableArray.CreateRange(outputs.Select(o => (Input<T>)o)));
 
         /// <summary>
         /// Takes in a <see cref="FormattableString"/> with potential <see cref="Input{T}"/>s or
diff --git a/sdk/dotnet/Pulumi/PublicAPI.Unshipped.txt b/sdk/dotnet/Pulumi/PublicAPI.Unshipped.txt
index c99f4a92a1ed..8cb2998fae8c 100644
--- a/sdk/dotnet/Pulumi/PublicAPI.Unshipped.txt
+++ b/sdk/dotnet/Pulumi/PublicAPI.Unshipped.txt
@@ -275,8 +275,10 @@ static Pulumi.Log.Error(string message, Pulumi.Resource resource = null, int? st
 static Pulumi.Log.Exception(System.Exception exception, Pulumi.Resource resource = null, int? streamId = null, bool? ephemeral = null) -> void
 static Pulumi.Log.Info(string message, Pulumi.Resource resource = null, int? streamId = null, bool? ephemeral = null) -> void
 static Pulumi.Log.Warn(string message, Pulumi.Resource resource = null, int? streamId = null, bool? ephemeral = null) -> void
-static Pulumi.Output.All<T>(System.Collections.Immutable.ImmutableArray<Pulumi.Input<T>> inputs) -> Pulumi.Output<System.Collections.Immutable.ImmutableArray<T>>
+static Pulumi.Output.All<T>(System.Collections.Generic.IEnumerable<Pulumi.Input<T>> inputs) -> Pulumi.Output<System.Collections.Immutable.ImmutableArray<T>>
+static Pulumi.Output.All<T>(System.Collections.Generic.IEnumerable<Pulumi.Output<T>> outputs) -> Pulumi.Output<System.Collections.Immutable.ImmutableArray<T>>
 static Pulumi.Output.All<T>(params Pulumi.Input<T>[] inputs) -> Pulumi.Output<System.Collections.Immutable.ImmutableArray<T>>
+static Pulumi.Output.All<T>(params Pulumi.Output<T>[] outputs) -> Pulumi.Output<System.Collections.Immutable.ImmutableArray<T>>
 static Pulumi.Output.Create<T>(System.Threading.Tasks.Task<T> value) -> Pulumi.Output<T>
 static Pulumi.Output.Create<T>(T value) -> Pulumi.Output<T>
 static Pulumi.Output.CreateSecret<T>(System.Threading.Tasks.Task<T> value) -> Pulumi.Output<T>