diff --git a/simulation/halsim_gui/CMakeLists.txt b/simulation/halsim_gui/CMakeLists.txt
index 91af53c7c0..f1804e458e 100644
--- a/simulation/halsim_gui/CMakeLists.txt
+++ b/simulation/halsim_gui/CMakeLists.txt
@@ -7,7 +7,7 @@ file(GLOB halsim_gui_src src/main/native/cpp/*.cpp)
 add_library(halsim_gui MODULE ${halsim_gui_src})
 wpilib_target_warnings(halsim_gui)
 set_target_properties(halsim_gui PROPERTIES DEBUG_POSTFIX "d")
-target_link_libraries(halsim_gui PUBLIC hal PRIVATE imgui)
+target_link_libraries(halsim_gui PUBLIC hal ntcore PRIVATE imgui)
 
 target_include_directories(halsim_gui PRIVATE src/main/native/include)
 
diff --git a/simulation/halsim_gui/build.gradle b/simulation/halsim_gui/build.gradle
index 5df53023dd..49a2f49d93 100644
--- a/simulation/halsim_gui/build.gradle
+++ b/simulation/halsim_gui/build.gradle
@@ -4,6 +4,7 @@ if (!project.hasProperty('onlylinuxathena') && !project.hasProperty('onlylinuxra
 
     ext {
         includeWpiutil = true
+        includeNtCore = true
         pluginName = 'halsim_gui'
     }
 
diff --git a/simulation/halsim_gui/src/main/native/cpp/NetworkTablesGui.cpp b/simulation/halsim_gui/src/main/native/cpp/NetworkTablesGui.cpp
new file mode 100644
index 0000000000..548b49a31c
--- /dev/null
+++ b/simulation/halsim_gui/src/main/native/cpp/NetworkTablesGui.cpp
@@ -0,0 +1,362 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2020 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#include "NetworkTablesGui.h"
+
+#include <cstdio>
+#include <cstring>
+#include <initializer_list>
+#include <memory>
+#include <vector>
+
+#include <imgui.h>
+#include <networktables/NetworkTableInstance.h>
+#include <networktables/NetworkTableValue.h>
+#include <wpi/Format.h>
+#include <wpi/SmallString.h>
+#include <wpi/StringRef.h>
+#include <wpi/raw_ostream.h>
+
+#include "HALSimGui.h"
+
+using namespace halsimgui;
+
+static void BooleanArrayToString(wpi::SmallVectorImpl<char>& out,
+                                 wpi::ArrayRef<int> in) {
+  out.clear();
+  wpi::raw_svector_ostream os{out};
+  os << '[';
+  bool first = true;
+  for (auto v : in) {
+    if (!first) os << ',';
+    first = false;
+    if (v)
+      os << "true";
+    else
+      os << "false";
+  }
+  os << ']';
+}
+
+static std::shared_ptr<nt::Value> StringToBooleanArray(wpi::StringRef in) {
+  in = in.trim();
+  if (in.empty())
+    return nt::NetworkTableValue::MakeBooleanArray(
+        std::initializer_list<bool>{});
+  if (in.front() == '[') in = in.drop_front();
+  if (in.back() == ']') in = in.drop_back();
+  in = in.trim();
+
+  wpi::SmallVector<wpi::StringRef, 16> inSplit;
+  wpi::SmallVector<int, 16> out;
+
+  in.split(inSplit, ',', -1, false);
+  for (auto val : inSplit) {
+    val = val.trim();
+    if (val.equals_lower("true")) {
+      out.emplace_back(1);
+    } else if (val.equals_lower("false")) {
+      out.emplace_back(0);
+    } else {
+      wpi::errs() << "GUI: NetworkTables: Could not understand value '" << val
+                  << "'\n";
+      return nullptr;
+    }
+  }
+
+  return nt::NetworkTableValue::MakeBooleanArray(out);
+}
+
+static void DoubleArrayToString(wpi::SmallVectorImpl<char>& out,
+                                wpi::ArrayRef<double> in) {
+  out.clear();
+  wpi::raw_svector_ostream os{out};
+  os << '[';
+  bool first = true;
+  for (auto v : in) {
+    if (!first) os << ',';
+    first = false;
+    os << wpi::format("%.6f", v);
+  }
+  os << ']';
+}
+
+static std::shared_ptr<nt::Value> StringToDoubleArray(wpi::StringRef in) {
+  in = in.trim();
+  if (in.empty())
+    return nt::NetworkTableValue::MakeBooleanArray(
+        std::initializer_list<bool>{});
+  if (in.front() == '[') in = in.drop_front();
+  if (in.back() == ']') in = in.drop_back();
+  in = in.trim();
+
+  wpi::SmallVector<wpi::StringRef, 16> inSplit;
+  wpi::SmallVector<double, 16> out;
+
+  in.split(inSplit, ',', -1, false);
+  for (auto val : inSplit) {
+    val = val.trim();
+    wpi::SmallString<32> valStr = val;
+    double d;
+    if (std::sscanf(valStr.c_str(), "%lf", &d) == 1) {
+      out.emplace_back(d);
+    } else {
+      wpi::errs() << "GUI: NetworkTables: Could not understand value '" << val
+                  << "'\n";
+      return nullptr;
+    }
+  }
+
+  return nt::NetworkTableValue::MakeDoubleArray(out);
+}
+
+static void StringArrayToString(wpi::SmallVectorImpl<char>& out,
+                                wpi::ArrayRef<std::string> in) {
+  out.clear();
+  wpi::raw_svector_ostream os{out};
+  os << '[';
+  bool first = true;
+  for (auto&& v : in) {
+    if (!first) os << ',';
+    first = false;
+    os << '"';
+    os.write_escaped(v);
+    os << '"';
+  }
+  os << ']';
+}
+
+static int fromxdigit(char ch) {
+  if (ch >= 'a' && ch <= 'f')
+    return (ch - 'a' + 10);
+  else if (ch >= 'A' && ch <= 'F')
+    return (ch - 'A' + 10);
+  else
+    return ch - '0';
+}
+
+static wpi::StringRef UnescapeString(wpi::StringRef source,
+                                     wpi::SmallVectorImpl<char>& buf) {
+  assert(source.size() >= 2 && source.front() == '"' && source.back() == '"');
+  buf.clear();
+  buf.reserve(source.size() - 2);
+  for (auto s = source.begin() + 1, end = source.end() - 1; s != end; ++s) {
+    if (*s != '\\') {
+      buf.push_back(*s);
+      continue;
+    }
+    switch (*++s) {
+      case 't':
+        buf.push_back('\t');
+        break;
+      case 'n':
+        buf.push_back('\n');
+        break;
+      case 'x': {
+        if (!isxdigit(*(s + 1))) {
+          buf.push_back('x');  // treat it like a unknown escape
+          break;
+        }
+        int ch = fromxdigit(*++s);
+        if (std::isxdigit(*(s + 1))) {
+          ch <<= 4;
+          ch |= fromxdigit(*++s);
+        }
+        buf.push_back(static_cast<char>(ch));
+        break;
+      }
+      default:
+        buf.push_back(*s);
+        break;
+    }
+  }
+  return wpi::StringRef{buf.data(), buf.size()};
+}
+
+static std::shared_ptr<nt::Value> StringToStringArray(wpi::StringRef in) {
+  in = in.trim();
+  if (in.empty())
+    return nt::NetworkTableValue::MakeStringArray(
+        std::initializer_list<std::string>{});
+  if (in.front() == '[') in = in.drop_front();
+  if (in.back() == ']') in = in.drop_back();
+  in = in.trim();
+
+  wpi::SmallVector<wpi::StringRef, 16> inSplit;
+  std::vector<std::string> out;
+  wpi::SmallString<32> buf;
+
+  in.split(inSplit, ',', -1, false);
+  for (auto val : inSplit) {
+    val = val.trim();
+    if (val.empty()) continue;
+    if (val.front() != '"' || val.back() != '"') {
+      wpi::errs() << "GUI: NetworkTables: Could not understand value '" << val
+                  << "'\n";
+      return nullptr;
+    }
+    out.emplace_back(UnescapeString(val, buf));
+  }
+
+  return nt::NetworkTableValue::MakeStringArray(std::move(out));
+}
+
+static constexpr size_t kTextBufferSize = 4096;
+
+static char* GetTextBuffer(wpi::StringRef in) {
+  static char textBuffer[kTextBufferSize];
+  size_t len = (std::min)(in.size(), kTextBufferSize - 1);
+  std::memcpy(textBuffer, in.data(), len);
+  textBuffer[len] = '\0';
+  return textBuffer;
+}
+
+static void DisplayNetworkTables() {
+  static auto inst = nt::NetworkTableInstance::GetDefault();
+
+  if (ImGui::CollapsingHeader("Connections")) {
+    ImGui::Columns(4, "connections");
+    ImGui::Text("Id");
+    ImGui::NextColumn();
+    ImGui::Text("Address");
+    ImGui::NextColumn();
+    ImGui::Text("Updated");
+    ImGui::NextColumn();
+    ImGui::Text("Proto");
+    ImGui::NextColumn();
+    ImGui::Separator();
+    for (auto&& i : inst.GetConnections()) {
+      ImGui::Text("%s", i.remote_id.c_str());
+      ImGui::NextColumn();
+      ImGui::Text("%s", i.remote_ip.c_str());
+      ImGui::NextColumn();
+      ImGui::Text("%llu",
+                  static_cast<unsigned long long>(  // NOLINT(runtime/int)
+                      i.last_update));
+      ImGui::NextColumn();
+      ImGui::Text("%d.%d", i.protocol_version >> 8, i.protocol_version & 0xff);
+      ImGui::NextColumn();
+    }
+    ImGui::Columns();
+  }
+
+  if (ImGui::CollapsingHeader("Values", ImGuiTreeNodeFlags_DefaultOpen)) {
+    static bool first = true;
+    ImGui::Columns(4, "values");
+    if (first) ImGui::SetColumnWidth(-1, 0.5f * ImGui::GetWindowWidth());
+    ImGui::Text("Name");
+    ImGui::NextColumn();
+    ImGui::Text("Value");
+    ImGui::NextColumn();
+    if (first) ImGui::SetColumnWidth(-1, 12 * ImGui::GetFontSize());
+    ImGui::Text("Flags");
+    ImGui::NextColumn();
+    ImGui::Text("Changed");
+    ImGui::NextColumn();
+    ImGui::Separator();
+    first = false;
+
+    auto info = inst.GetEntryInfo("", 0);
+    std::sort(info.begin(), info.end(),
+              [](const auto& a, const auto& b) { return a.name < b.name; });
+
+    for (auto&& i : info) {
+      ImGui::Text("%s", i.name.c_str());
+      ImGui::NextColumn();
+
+      if (auto val = nt::GetEntryValue(i.entry)) {
+        ImGui::PushID(i.name.c_str());
+        switch (val->type()) {
+          case NT_BOOLEAN: {
+            static const char* boolOptions[] = {"false", "true"};
+            int v = val->GetBoolean() ? 1 : 0;
+            if (ImGui::Combo("boolean", &v, boolOptions, 2))
+              nt::SetEntryValue(i.entry, nt::NetworkTableValue::MakeBoolean(v));
+            break;
+          }
+          case NT_DOUBLE: {
+            double v = val->GetDouble();
+            if (ImGui::InputDouble("double", &v, 0, 0, "%.6f",
+                                   ImGuiInputTextFlags_EnterReturnsTrue))
+              nt::SetEntryValue(i.entry, nt::NetworkTableValue::MakeDouble(v));
+            break;
+          }
+          case NT_STRING: {
+            char* v = GetTextBuffer(val->GetString());
+            if (ImGui::InputText("string", v, kTextBufferSize,
+                                 ImGuiInputTextFlags_EnterReturnsTrue))
+              nt::SetEntryValue(i.entry, nt::NetworkTableValue::MakeString(v));
+            break;
+          }
+          case NT_BOOLEAN_ARRAY: {
+            wpi::SmallString<64> buf;
+            BooleanArrayToString(buf, val->GetBooleanArray());
+            char* v = GetTextBuffer(buf);
+            if (ImGui::InputText("boolean[]", v, kTextBufferSize,
+                                 ImGuiInputTextFlags_EnterReturnsTrue)) {
+              if (auto outv = StringToBooleanArray(v))
+                nt::SetEntryValue(i.entry, std::move(outv));
+            }
+            break;
+          }
+          case NT_DOUBLE_ARRAY: {
+            wpi::SmallString<64> buf;
+            DoubleArrayToString(buf, val->GetDoubleArray());
+            char* v = GetTextBuffer(buf);
+            if (ImGui::InputText("double[]", v, kTextBufferSize,
+                                 ImGuiInputTextFlags_EnterReturnsTrue)) {
+              if (auto outv = StringToDoubleArray(v))
+                nt::SetEntryValue(i.entry, std::move(outv));
+            }
+            break;
+          }
+          case NT_STRING_ARRAY: {
+            wpi::SmallString<64> buf;
+            StringArrayToString(buf, val->GetStringArray());
+            char* v = GetTextBuffer(buf);
+            if (ImGui::InputText("string[]", v, kTextBufferSize,
+                                 ImGuiInputTextFlags_EnterReturnsTrue)) {
+              if (auto outv = StringToStringArray(v))
+                nt::SetEntryValue(i.entry, std::move(outv));
+            }
+            break;
+          }
+          case NT_RAW:
+            ImGui::LabelText("raw", "[...]");
+            break;
+          case NT_RPC:
+            ImGui::LabelText("rpc", "[...]");
+            break;
+          default:
+            ImGui::LabelText("other", "?");
+            break;
+        }
+        ImGui::PopID();
+      }
+      ImGui::NextColumn();
+
+      if ((i.flags & NT_PERSISTENT) != 0)
+        ImGui::Text("Persistent");
+      else if (i.flags != 0)
+        ImGui::Text("%02x", i.flags);
+      ImGui::NextColumn();
+
+      ImGui::Text("%llu",
+                  static_cast<unsigned long long>(  // NOLINT(runtime/int)
+                      i.last_change));
+      ImGui::NextColumn();
+      ImGui::Separator();
+    }
+    ImGui::Columns();
+  }
+}
+
+void NetworkTablesGui::Initialize() {
+  HALSimGui::AddWindow("NetworkTables", DisplayNetworkTables);
+  HALSimGui::SetDefaultWindowPos("NetworkTables", 250, 260);
+  HALSimGui::SetDefaultWindowSize("NetworkTables", 1500, 375);
+}
diff --git a/simulation/halsim_gui/src/main/native/cpp/NetworkTablesGui.h b/simulation/halsim_gui/src/main/native/cpp/NetworkTablesGui.h
new file mode 100644
index 0000000000..f4e5d7baeb
--- /dev/null
+++ b/simulation/halsim_gui/src/main/native/cpp/NetworkTablesGui.h
@@ -0,0 +1,17 @@
+/*----------------------------------------------------------------------------*/
+/* Copyright (c) 2020 FIRST. All Rights Reserved.                             */
+/* Open Source Software - may be modified and shared by FRC teams. The code   */
+/* must be accompanied by the FIRST BSD license file in the root directory of */
+/* the project.                                                               */
+/*----------------------------------------------------------------------------*/
+
+#pragma once
+
+namespace halsimgui {
+
+class NetworkTablesGui {
+ public:
+  static void Initialize();
+};
+
+}  // namespace halsimgui
diff --git a/simulation/halsim_gui/src/main/native/cpp/main.cpp b/simulation/halsim_gui/src/main/native/cpp/main.cpp
index 2362d34311..acbfbd6c29 100644
--- a/simulation/halsim_gui/src/main/native/cpp/main.cpp
+++ b/simulation/halsim_gui/src/main/native/cpp/main.cpp
@@ -19,6 +19,7 @@
 #include "EncoderGui.h"
 #include "Field2D.h"
 #include "HALSimGui.h"
+#include "NetworkTablesGui.h"
 #include "PDPGui.h"
 #include "PWMGui.h"
 #include "RelayGui.h"
@@ -44,6 +45,7 @@ __declspec(dllexport)
   HALSimGui::Add(DIOGui::Initialize);
   HALSimGui::Add(EncoderGui::Initialize);
   HALSimGui::Add(Field2D::Initialize);
+  HALSimGui::Add(NetworkTablesGui::Initialize);
   HALSimGui::Add(PDPGui::Initialize);
   HALSimGui::Add(PWMGui::Initialize);
   HALSimGui::Add(RelayGui::Initialize);