diff --git a/buffer.go b/buffer.go
index 659a63e..fee6658 100644
--- a/buffer.go
+++ b/buffer.go
@@ -1,5 +1,7 @@
 package stone
 
+import "sync"
+
 // Color represents all the different colors a cell can be.
 type Color uint8
 
@@ -65,6 +67,10 @@ type Buffer struct {
 		x int
 		y int
 	}
+
+	// This should be write locked when resizing the buffer, and read locked
+	// when writing to cells or reading information about the buffer.
+	lock sync.RWMutex
 }
 
 func (buffer *Buffer) isOutOfBounds (x, y int) (outOfBounds bool) {
@@ -78,6 +84,9 @@ func (buffer *Buffer) isOutOfBounds (x, y int) (outOfBounds bool) {
 
 // Size returns the width and height of the buffer.
 func (buffer *Buffer) Size () (width, height int) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	width  = buffer.width
 	height = buffer.height
 	return
@@ -93,6 +102,9 @@ func (buffer *Buffer) SetDot (x, y int) {
 // Cell returns the cell at the specified x and y coordinates. If the
 // coordinates are out of bounds, this method will return a blank cell.
 func (buffer *Buffer) Cell (x, y int) (cell Cell) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	if buffer.isOutOfBounds(x, y) { return }
 	cell = buffer.content[x + y * buffer.width]
 	return
@@ -100,6 +112,9 @@ func (buffer *Buffer) Cell (x, y int) (cell Cell) {
 
 // SetColor sets the color of the cell at the specified x and y coordinates.
 func (buffer *Buffer) SetColor (x, y int, color Color) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	if buffer.isOutOfBounds(x, y) { return }
 	index := x + y * buffer.width
 	buffer.clean[index] = buffer.content[index].color == color
@@ -109,6 +124,9 @@ func (buffer *Buffer) SetColor (x, y int, color Color) {
 // SetSize sets the width and height of the buffer. This clears all data in the
 // buffer. If the width or height is negative, this method does nothing.
 func (buffer *Buffer) SetSize (width, height int) {
+	buffer.lock.Lock()
+	defer buffer.lock.Unlock()
+	
 	if width < 0 || height < 0 { return }
 	buffer.width   = width
 	buffer.height  = height
@@ -121,6 +139,9 @@ func (buffer *Buffer) SetSize (width, height int) {
 
 // SetStyle sets the style of the cell at the specified x and y coordinates.
 func (buffer *Buffer) SetStyle (x, y int, style Style) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	if buffer.isOutOfBounds(x, y) { return }
 	index := x + y * buffer.width
 	buffer.clean[index] = buffer.content[index].style == style
@@ -129,6 +150,9 @@ func (buffer *Buffer) SetStyle (x, y int, style Style) {
 
 // SetRune sets the rune of the cell at the specified x and y coordinates.
 func (buffer *Buffer) SetRune (x, y int, content rune) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	if buffer.isOutOfBounds(x, y) { return }
 	index := x + y * buffer.width
 	buffer.clean[index] = buffer.content[index].content == content
@@ -138,6 +162,9 @@ func (buffer *Buffer) SetRune (x, y int, content rune) {
 // Write writes data stored in a byte slice to the buffer at the current dot
 // position. This makes Buffer an io.Writer.
 func (buffer *Buffer) Write (bytes []byte) (bytesWritten int, err error) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	text := string(bytes)
 	bytesWritten = len(bytes)
 	
@@ -153,6 +180,9 @@ func (buffer *Buffer) Write (bytes []byte) (bytesWritten int, err error) {
 // Clean returns whether or not the cell at the specified x and y coordinates is
 // clean.
 func (buffer *Buffer) Clean (x, y int) (clean bool) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	if buffer.isOutOfBounds(x, y) { return }
 	clean = buffer.clean[x + y * buffer.width]
 	return
@@ -160,6 +190,9 @@ func (buffer *Buffer) Clean (x, y int) (clean bool) {
 
 // MarkClean marks the cell at the specified x and y coordinates as clean.
 func (buffer *Buffer) MarkClean (x, y int) {
+	buffer.lock.RLock()
+	defer buffer.lock.RUnlock()
+	
 	if buffer.isOutOfBounds(x, y) { return }
 	buffer.clean[x + y * buffer.width] = true
 }