diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/Logger.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/Logger.kt
new file mode 100644
index 000000000..434a1b419
--- /dev/null
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/Logger.kt
@@ -0,0 +1,6 @@
+package com.novoda.gol
+
+expect object Logger {
+
+    fun log(o: Any?)
+}
diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppModel.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppModel.kt
new file mode 100644
index 000000000..963cb7dc3
--- /dev/null
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppModel.kt
@@ -0,0 +1,28 @@
+package com.novoda.gol.presentation
+
+import com.novoda.gol.patterns.PatternEntity
+import kotlin.properties.Delegates.observable
+
+class AppModel {
+
+    private var boardViewState by observable(BoardViewState(true)) { _, _, newValue ->
+        onBoardStateChanged(newValue)
+    }
+
+    var onSimulationStateChanged: (isIdle: Boolean) -> Unit by observable<(Boolean) -> Unit>({}) { _, _, newValue ->
+        newValue(boardViewState.isIdle)
+    }
+
+    var onBoardStateChanged: (BoardViewState) -> Unit by observable<(BoardViewState) -> Unit>({}) { _, _, newValue ->
+        newValue(boardViewState)
+    }
+
+    fun toggleSimulation() {
+        boardViewState = BoardViewState(isIdle = boardViewState.isIdle.not())
+        onSimulationStateChanged(boardViewState.isIdle)
+    }
+
+    fun selectPattern(pattern: PatternEntity) {
+        boardViewState = boardViewState.copy(selectedPattern = pattern)
+    }
+}
diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppPresenter.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppPresenter.kt
new file mode 100644
index 000000000..08f525f7a
--- /dev/null
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppPresenter.kt
@@ -0,0 +1,25 @@
+package com.novoda.gol.presentation
+
+class AppPresenter {
+
+    private val model = AppModel()
+
+    fun bind(view: AppView) {
+
+        model.onSimulationStateChanged = { isIdle ->
+            view.renderControlButtonLabel(if (isIdle) "Start simulation" else "Stop Simulation")
+            view.renderPatternSelectionVisibility(visibility = isIdle)
+        }
+
+        model.onBoardStateChanged = view::renderBoard
+
+        view.onControlButtonClicked = model::toggleSimulation
+
+        view.onPatternSelected = model::selectPattern
+    }
+
+    fun unbind(view: AppView) {
+        model.onSimulationStateChanged = {}
+        view.onControlButtonClicked = {}
+    }
+}
diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppView.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppView.kt
new file mode 100644
index 000000000..510570870
--- /dev/null
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/AppView.kt
@@ -0,0 +1,13 @@
+package com.novoda.gol.presentation
+
+import com.novoda.gol.patterns.PatternEntity
+
+interface AppView {
+
+    var onControlButtonClicked : () -> Unit
+    var onPatternSelected: (pattern : PatternEntity) -> Unit
+
+    fun renderControlButtonLabel(controlButtonLabel: String)
+    fun renderPatternSelectionVisibility(visibility: Boolean)
+    fun renderBoard(boardViewState: BoardViewState)
+}
diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardModelImpl.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardModelImpl.kt
index ac09a999c..b8d92b997 100644
--- a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardModelImpl.kt
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardModelImpl.kt
@@ -34,7 +34,7 @@ class BoardModelImpl private constructor(initialBoard: BoardEntity, private val
     }
 
     override fun selectPattern(pattern: PatternEntity) {
-        if (gameLoop.isLooping() || this.pattern == pattern) {
+        if (gameLoop.isLooping()) {
             return
         }
         this.pattern = pattern
diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardViewState.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardViewState.kt
new file mode 100644
index 000000000..b27a98f1e
--- /dev/null
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/BoardViewState.kt
@@ -0,0 +1,8 @@
+package com.novoda.gol.presentation
+
+import com.novoda.gol.patterns.PatternEntity
+
+data class BoardViewState(
+        val isIdle: Boolean,
+        val selectedPattern: PatternEntity? = null
+)
diff --git a/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/PatternViewState.kt b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/PatternViewState.kt
new file mode 100644
index 000000000..4ea6cf003
--- /dev/null
+++ b/game-of-life-multiplatform/common/src/main/kotlin/com/novoda/gol/presentation/PatternViewState.kt
@@ -0,0 +1,8 @@
+package com.novoda.gol.presentation
+
+import com.novoda.gol.patterns.PatternEntity
+
+data class PatternViewState(
+        var shouldDisplay: Boolean,
+        val patternEntities: List<PatternEntity>
+)
diff --git a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/Logger.kt b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/Logger.kt
new file mode 100644
index 000000000..efb463bf3
--- /dev/null
+++ b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/Logger.kt
@@ -0,0 +1,8 @@
+package com.novoda.gol
+
+actual object Logger {
+
+    actual fun log(o: Any?) {
+        console.log(o)
+    }
+}
diff --git a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/App.kt b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/App.kt
index 82d924f72..ea4e8727a 100644
--- a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/App.kt
+++ b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/App.kt
@@ -4,16 +4,50 @@ package com.novoda.gol.components
 
 import com.novoda.gol.patterns.PatternEntity
 import com.novoda.gol.patterns.PatternRepository
+import com.novoda.gol.presentation.AppPresenter
+import com.novoda.gol.presentation.AppView
+import com.novoda.gol.presentation.BoardViewState
+import com.novoda.gol.presentation.PatternViewState
 import kotlinx.html.style
 import react.*
 import react.dom.div
 import react.dom.h2
 
-class App : RComponent<RProps, State>() {
+class App : RComponent<RProps, State>(), AppView {
+
+    override var onControlButtonClicked: () -> Unit = {}
+    override var onPatternSelected: (pattern: PatternEntity) -> Unit = {}
+
+    private val presenter: AppPresenter = AppPresenter()
+
+    override fun componentWillMount() {
+        presenter.bind(this)
+    }
+
+    override fun componentWillUnmount() {
+        presenter.unbind(this)
+    }
 
     override fun State.init() {
-        patternEntities = PatternRepository.patterns()
-        isIdle = true
+        patternViewState = PatternViewState(true, PatternRepository.patterns())
+    }
+
+    override fun renderControlButtonLabel(controlButtonLabel: String) {
+        setState {
+            this.controlButtonLabel = controlButtonLabel
+        }
+    }
+
+    override fun renderPatternSelectionVisibility(visibility: Boolean) {
+        setState {
+            patternViewState.shouldDisplay = visibility
+        }
+    }
+
+    override fun renderBoard(boardViewState: BoardViewState) {
+        setState {
+            this.boardViewState = boardViewState
+        }
     }
 
     override fun RBuilder.render(): ReactElement? =
@@ -23,10 +57,8 @@ class App : RComponent<RProps, State>() {
                     flexDirection = "column"
                 }
 
-                controlButton(controlButtonLabel(), {
-                    setState {
-                        isIdle = isIdle.not()
-                    }
+                controlButton(state.controlButtonLabel, {
+                    onControlButtonClicked()
                 })
 
                 div {
@@ -34,9 +66,9 @@ class App : RComponent<RProps, State>() {
                         display = "flex"
                     }
 
-                    board(state.isIdle, state.selectedPattern)
+                    board(state.boardViewState)
 
-                    if (state.isIdle) {
+                    if (state.patternViewState.shouldDisplay) {
 
                         div {
 
@@ -46,26 +78,21 @@ class App : RComponent<RProps, State>() {
 
                             h2 { +"Choose a pattern" }
 
-                            for (patternEntity in state.patternEntities) {
-                                pattern(patternEntity, {
-                                    setState {
-                                        selectedPattern = patternEntity
-                                    }
+                            state.patternViewState.patternEntities.forEach { pattern ->
+                                pattern(pattern, {
+                                    onPatternSelected(pattern)
                                 })
                             }
                         }
                     }
                 }
             }
-
-    private fun controlButtonLabel() = if (state.isIdle) "Start simulation" else "Stop Simulation"
-
 }
 
 interface State : RState {
-    var patternEntities: List<PatternEntity>
-    var isIdle: Boolean
-    var selectedPattern: PatternEntity?
+    var patternViewState: PatternViewState
+    var boardViewState: BoardViewState
+    var controlButtonLabel: String
 }
 
 fun RBuilder.app() = child(App::class) {}
diff --git a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/Board.kt b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/Board.kt
index 1f3275c76..6bac1fca5 100644
--- a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/Board.kt
+++ b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/Board.kt
@@ -7,6 +7,7 @@ import com.novoda.gol.data.PositionEntity
 import com.novoda.gol.patterns.PatternEntity
 import com.novoda.gol.presentation.BoardPresenter
 import com.novoda.gol.presentation.BoardView
+import com.novoda.gol.presentation.BoardViewState
 import kotlinext.js.js
 import kotlinx.html.style
 import react.*
@@ -39,18 +40,22 @@ class Board(boardProps: BoardProps) : RComponent<BoardProps, BoardState>(boardPr
     override fun BoardState.init(props: BoardProps) {
         presenter = BoardPresenter(50, 50)
 
-        if (props.selectedPattern != null) {
-            onPatternSelected.invoke(props.selectedPattern!!)
+        if (props.boardViewState.selectedPattern != null) {
+            onPatternSelected.invoke(props.boardViewState.selectedPattern!!)
         }
     }
 
     override fun componentWillReceiveProps(nextProps: BoardProps) {
-        if (nextProps.isIdle.not()) {
+        val state = nextProps.boardViewState
+
+        if (state.isIdle.not()) {
             onStartSimulationClicked()
         } else {
             onStopSimulationClicked()
         }
-        onPatternSelected.invoke(nextProps.selectedPattern!!)
+        if (state.selectedPattern != null) {
+            onPatternSelected.invoke(state.selectedPattern!!)
+        }
     }
 
     override fun RBuilder.render() = renderBoard(state)
@@ -74,16 +79,12 @@ class Board(boardProps: BoardProps) : RComponent<BoardProps, BoardState>(boardPr
     }
 }
 
-data class BoardProps(var isIdle: Boolean, var selectedPattern: PatternEntity? = null) : RProps
+data class BoardProps(var boardViewState: BoardViewState) : RProps
 
 interface BoardState : RState {
     var boardEntity: BoardEntity
 }
 
-fun RBuilder.board(isIdle: Boolean, selectedPattern: PatternEntity? = null) = child(
-        Board::class) {
-    attrs.isIdle = isIdle
-    attrs.selectedPattern = selectedPattern
+fun RBuilder.board(board: BoardViewState) = child(Board::class) {
+    attrs.boardViewState = board
 }
-
-
diff --git a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/pattern.kt b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/pattern.kt
index fb64cb5e2..97dbbc16b 100644
--- a/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/pattern.kt
+++ b/game-of-life-multiplatform/game-of-life-js/src/main/kotlin/com/novoda/gol/components/pattern.kt
@@ -43,4 +43,4 @@ fun RBuilder.pattern(patternEntity: PatternEntity, onPatternSelected: () -> Unit
             }
         }
     }
-}
\ No newline at end of file
+}
diff --git a/game-of-life-multiplatform/game-of-life-jvm/src/main/kotlin/com/novoda/gol/Logger.kt b/game-of-life-multiplatform/game-of-life-jvm/src/main/kotlin/com/novoda/gol/Logger.kt
new file mode 100644
index 000000000..18620a6ea
--- /dev/null
+++ b/game-of-life-multiplatform/game-of-life-jvm/src/main/kotlin/com/novoda/gol/Logger.kt
@@ -0,0 +1,9 @@
+package com.novoda.gol
+
+actual object Logger {
+
+    actual fun log(o: Any?) {
+        System.out.println(o)
+    }
+
+}