diff --git a/cachematrix.R b/cachematrix.R
index a50be65aa44..ef0b4ae92dd 100644
--- a/cachematrix.R
+++ b/cachematrix.R
@@ -4,7 +4,15 @@
 ## Write a short comment describing this function
 
 makeCacheMatrix <- function(x = matrix()) {
-
+      inv <- NULL          ## initialize inv as NULL; will hold value of inverse matrix  
+      set <- function(y) { ## set to assign new  function
+            x <<- y        ## value of matrix in parent environment
+            inv <<- NULL   ## if there is a new matrix, reset inv to NULL
+      }
+      get <- function() {x} ## define the get function - returns value of the matrix argument
+      setInverse <- function(inverse) {inv <<- inverse} ## assigns value of inv in parent environment
+      getInverse <- function() {inv}  ## gets the value of inv where called
+      list(set = set, get = get, setInverse = setInverse, getInverse = getInverse)
 }
 
 
@@ -12,4 +20,13 @@ makeCacheMatrix <- function(x = matrix()) {
 
 cacheSolve <- function(x, ...) {
         ## Return a matrix that is the inverse of 'x'
+      inv <- x$getInverse()
+      if(!is.null(inv)) {    ## if inverse has not been already cached, it is cached and collected
+            message("cached data collected") 
+            return(inv)
+      }
+      m <- x$get()
+      inv <- solve(m, ...)
+      x$setInverse(inv)
+      inv
 }