Finishing documentation
diff --git a/openstack/networking/v2/subnets/doc.go b/openstack/networking/v2/subnets/doc.go
index b15101b..43e8296 100644
--- a/openstack/networking/v2/subnets/doc.go
+++ b/openstack/networking/v2/subnets/doc.go
@@ -1 +1,10 @@
+// Package subnets contains functionality for working with Neutron subnet
+// resources. A subnet represents an IP address block that can be used to
+// assign IP addresses to virtual instances. Each subnet must have a CIDR and
+// must be associated with a network. IPs can either be selected from the whole
+// subnet CIDR or from allocation pools specified by the user.
+//
+// A subnet can also have a gateway, a list of DNS name servers, and host routes.
+// This information is pushed to instances whose interfaces are associated with
+// the subnet.
 package subnets
diff --git a/openstack/networking/v2/subnets/errors.go b/openstack/networking/v2/subnets/errors.go
index ca2df72..0db0a6e 100644
--- a/openstack/networking/v2/subnets/errors.go
+++ b/openstack/networking/v2/subnets/errors.go
@@ -7,9 +7,7 @@
 }
 
 var (
-	ErrNetworkIDRequired     = err("A network ID is required")
-	ErrCIDRRequired          = err("A valid CIDR is required")
-	ErrInvalidIPType         = err("An IP type must either be 4 or 6")
-	ErrCIDRNotUpdatable      = err("CIDR attributes cannot be updated")
-	ErrIPVersionNotUpdatable = err("IP Version attributes cannot be updated")
+	errNetworkIDRequired = err("A network ID is required")
+	errCIDRRequired      = err("A valid CIDR is required")
+	errInvalidIPType     = err("An IP type must either be 4 or 6")
 )
diff --git a/openstack/networking/v2/subnets/requests.go b/openstack/networking/v2/subnets/requests.go
index ff36765..5a07863 100644
--- a/openstack/networking/v2/subnets/requests.go
+++ b/openstack/networking/v2/subnets/requests.go
@@ -9,6 +9,18 @@
 	"github.com/rackspace/gophercloud/pagination"
 )
 
+func maybeString(original string) *string {
+	if original != "" {
+		return &original
+	}
+	return nil
+}
+
+// ListOpts allows the filtering and sorting of paginated collections through
+// the API. Filtering is achieved by passing in struct field values that map to
+// the subnet attributes you want to see returned. SortKey allows you to sort
+// by a particular subnet attribute. SortDir sets the direction, and is either
+// `asc' or `desc'. Marker and Limit are used for pagination.
 type ListOpts struct {
 	Name       string
 	EnableDHCP *bool
@@ -19,12 +31,18 @@
 	CIDR       string
 	ID         string
 	Limit      int
-	Page       string
-	PerPage    string
+	Marker     string
 	SortKey    string
 	SortDir    string
 }
 
+// List returns a Pager which allows you to iterate over a collection of
+// subnets. It accepts a ListOpts struct, which allows you to filter and sort
+// the returned collection for greater efficiency.
+//
+// Default policy settings return only those subnets that are owned by the tenant
+// who submits the request, unless the request is submitted by an user with
+// administrative rights.
 func List(c *gophercloud.ServiceClient, opts ListOpts) pagination.Pager {
 	// Build query parameters
 	q := make(map[string]string)
@@ -55,11 +73,8 @@
 	if opts.Limit != 0 {
 		q["limit"] = strconv.Itoa(opts.Limit)
 	}
-	if opts.Page != "" {
-		q["page"] = opts.Page
-	}
-	if opts.PerPage != "" {
-		q["per_page"] = opts.PerPage
+	if opts.Marker != "" {
+		q["marker"] = opts.Marker
 	}
 	if opts.SortKey != "" {
 		q["sort_key"] = opts.SortKey
@@ -68,15 +83,16 @@
 		q["sort_dir"] = opts.SortDir
 	}
 
-	u := ListURL(c) + utils.BuildQuery(q)
+	u := listURL(c) + utils.BuildQuery(q)
 	return pagination.NewPager(c, u, func(r pagination.LastHTTPResponse) pagination.Page {
 		return SubnetPage{pagination.LinkedPageBase(r)}
 	})
 }
 
+// Get retrieves a specific subnet based on its unique ID.
 func Get(c *gophercloud.ServiceClient, id string) (*Subnet, error) {
 	var s Subnet
-	_, err := perigee.Request("GET", GetURL(c, id), perigee.Options{
+	_, err := perigee.Request("GET", getURL(c, id), perigee.Options{
 		MoreHeaders: c.Provider.AuthenticatedHeaders(),
 		Results: &struct {
 			Subnet *Subnet `json:"subnet"`
@@ -89,19 +105,13 @@
 	return &s, nil
 }
 
-// maybeString returns nil for empty strings and nil for empty.
-func maybeString(original string) *string {
-	if original != "" {
-		return &original
-	}
-	return nil
-}
-
+// Valid IP types
 const (
 	IPv4 = 4
 	IPv6 = 6
 )
 
+// CreateOpts represents the attributes used when creating a new subnet.
 type CreateOpts struct {
 	// Required
 	NetworkID string
@@ -117,16 +127,18 @@
 	HostRoutes      []interface{}
 }
 
+// Create accepts a CreateOpts struct and creates a new subnet using the values
+// provided. You must remember to provide a valid NetworkID, CIDR and IP version.
 func Create(c *gophercloud.ServiceClient, opts CreateOpts) (*Subnet, error) {
 	// Validate required options
 	if opts.NetworkID == "" {
-		return nil, ErrNetworkIDRequired
+		return nil, errNetworkIDRequired
 	}
 	if opts.CIDR == "" {
-		return nil, ErrCIDRRequired
+		return nil, errCIDRRequired
 	}
 	if opts.IPVersion != 0 && opts.IPVersion != IPv4 && opts.IPVersion != IPv6 {
-		return nil, ErrInvalidIPType
+		return nil, errInvalidIPType
 	}
 
 	type subnet struct {
@@ -172,7 +184,7 @@
 	}
 
 	var res response
-	_, err := perigee.Request("POST", CreateURL(c), perigee.Options{
+	_, err := perigee.Request("POST", createURL(c), perigee.Options{
 		MoreHeaders: c.Provider.AuthenticatedHeaders(),
 		ReqBody:     &reqBody,
 		Results:     &res,
@@ -185,6 +197,7 @@
 	return res.Subnet, nil
 }
 
+// UpdateOpts represents the attributes used when updating an existing subnet.
 type UpdateOpts struct {
 	Name           string
 	GatewayIP      string
@@ -193,6 +206,8 @@
 	EnableDHCP     *bool
 }
 
+// Update accepts a UpdateOpts struct and updates an existing subnet using the
+// values provided.
 func Update(c *gophercloud.ServiceClient, id string, opts UpdateOpts) (*Subnet, error) {
 	type subnet struct {
 		Name           *string       `json:"name,omitempty"`
@@ -224,7 +239,7 @@
 	}
 
 	var res response
-	_, err := perigee.Request("PUT", UpdateURL(c, id), perigee.Options{
+	_, err := perigee.Request("PUT", updateURL(c, id), perigee.Options{
 		MoreHeaders: c.Provider.AuthenticatedHeaders(),
 		ReqBody:     &reqBody,
 		Results:     &res,
@@ -237,8 +252,9 @@
 	return res.Subnet, nil
 }
 
+// Delete accepts a unique ID and deletes the subnet associated with it.
 func Delete(c *gophercloud.ServiceClient, id string) error {
-	_, err := perigee.Request("DELETE", DeleteURL(c, id), perigee.Options{
+	_, err := perigee.Request("DELETE", deleteURL(c, id), perigee.Options{
 		MoreHeaders: c.Provider.AuthenticatedHeaders(),
 		OkCodes:     []int{204},
 	})
diff --git a/openstack/networking/v2/subnets/results.go b/openstack/networking/v2/subnets/results.go
index d916a1c..f89bb3b 100644
--- a/openstack/networking/v2/subnets/results.go
+++ b/openstack/networking/v2/subnets/results.go
@@ -5,11 +5,14 @@
 	"github.com/rackspace/gophercloud/pagination"
 )
 
+// AllocationPool is a sub-struct that represents an allocation pool
 type AllocationPool struct {
 	Start string `json:"start"`
 	End   string `json:"end"`
 }
 
+// Subnet represents a subnet. See package documentation for a top-level
+// description of what this is.
 type Subnet struct {
 	// UUID representing the subnet
 	ID string `mapstructure:"id" json:"id"`
@@ -35,11 +38,16 @@
 	TenantID string `mapstructure:"tenant_id" json:"tenant_id"`
 }
 
+// SubnetPage is the page returned by a pager when traversing over a collection
+// of subnets.
 type SubnetPage struct {
 	pagination.LinkedPageBase
 }
 
-func (current SubnetPage) NextPageURL() (string, error) {
+// NextPageURL is invoked when a paginated collection of subnets has reached
+// the end of a page and the pager seeks to traverse over a new one. In order
+// to do this, it needs to construct the next page's URL.
+func (p SubnetPage) NextPageURL() (string, error) {
 	type link struct {
 		Href string `mapstructure:"href"`
 		Rel  string `mapstructure:"rel"`
@@ -49,7 +57,7 @@
 	}
 
 	var r resp
-	err := mapstructure.Decode(current.Body, &r)
+	err := mapstructure.Decode(p.Body, &r)
 	if err != nil {
 		return "", err
 	}
@@ -67,14 +75,18 @@
 	return url, nil
 }
 
-func (r SubnetPage) IsEmpty() (bool, error) {
-	is, err := ExtractSubnets(r)
+// IsEmpty checks whether a SubnetPage struct is empty.
+func (p SubnetPage) IsEmpty() (bool, error) {
+	is, err := ExtractSubnets(p)
 	if err != nil {
 		return true, nil
 	}
 	return len(is) == 0, nil
 }
 
+// ExtractSubnets accepts a Page struct, specifically a SubnetPage struct,
+// and extracts the elements into a slice of Subnet structs. In other words,
+// a generic collection is mapped into a relevant slice.
 func ExtractSubnets(page pagination.Page) ([]Subnet, error) {
 	var resp struct {
 		Subnets []Subnet `mapstructure:"subnets" json:"subnets"`
diff --git a/openstack/networking/v2/subnets/urls.go b/openstack/networking/v2/subnets/urls.go
index fe20c53..ca70b66 100644
--- a/openstack/networking/v2/subnets/urls.go
+++ b/openstack/networking/v2/subnets/urls.go
@@ -2,32 +2,32 @@
 
 import "github.com/rackspace/gophercloud"
 
-const Version = "v2.0"
+const version = "v2.0"
 
-func ResourceURL(c *gophercloud.ServiceClient, id string) string {
-	return c.ServiceURL(Version, "subnets", id)
+func resourceURL(c *gophercloud.ServiceClient, id string) string {
+	return c.ServiceURL(version, "subnets", id)
 }
 
-func RootURL(c *gophercloud.ServiceClient) string {
-	return c.ServiceURL(Version, "subnets")
+func rootURL(c *gophercloud.ServiceClient) string {
+	return c.ServiceURL(version, "subnets")
 }
 
-func ListURL(c *gophercloud.ServiceClient) string {
-	return RootURL(c)
+func listURL(c *gophercloud.ServiceClient) string {
+	return rootURL(c)
 }
 
-func GetURL(c *gophercloud.ServiceClient, id string) string {
-	return ResourceURL(c, id)
+func getURL(c *gophercloud.ServiceClient, id string) string {
+	return resourceURL(c, id)
 }
 
-func CreateURL(c *gophercloud.ServiceClient) string {
-	return RootURL(c)
+func createURL(c *gophercloud.ServiceClient) string {
+	return rootURL(c)
 }
 
-func UpdateURL(c *gophercloud.ServiceClient, id string) string {
-	return ResourceURL(c, id)
+func updateURL(c *gophercloud.ServiceClient, id string) string {
+	return resourceURL(c, id)
 }
 
-func DeleteURL(c *gophercloud.ServiceClient, id string) string {
-	return ResourceURL(c, id)
+func deleteURL(c *gophercloud.ServiceClient, id string) string {
+	return resourceURL(c, id)
 }
diff --git a/openstack/networking/v2/subnets/urls_tests.go b/openstack/networking/v2/subnets/urls_tests.go
index eec5275..b04b432 100644
--- a/openstack/networking/v2/subnets/urls_tests.go
+++ b/openstack/networking/v2/subnets/urls_tests.go
@@ -7,38 +7,38 @@
 	th "github.com/rackspace/gophercloud/testhelper"
 )
 
-const Endpoint = "http://localhost:57909/"
+const endpoint = "http://localhost:57909/"
 
-func EndpointClient() *gophercloud.ServiceClient {
-	return &gophercloud.ServiceClient{Endpoint: Endpoint}
+func endpointClient() *gophercloud.ServiceClient {
+	return &gophercloud.ServiceClient{Endpoint: endpoint}
 }
 
 func TestListURL(t *testing.T) {
-	actual := ListURL(EndpointClient())
-	expected := Endpoint + "v2.0/subnets"
+	actual := listURL(endpointClient())
+	expected := endpoint + "v2.0/subnets"
 	th.AssertEquals(t, expected, actual)
 }
 
 func TestGetURL(t *testing.T) {
-	actual := GetURL(EndpointClient(), "foo")
-	expected := Endpoint + "v2.0/subnets/foo"
+	actual := getURL(endpointClient(), "foo")
+	expected := endpoint + "v2.0/subnets/foo"
 	th.AssertEquals(t, expected, actual)
 }
 
 func TestCreateURL(t *testing.T) {
-	actual := CreateURL(EndpointClient())
-	expected := Endpoint + "v2.0/subnets"
+	actual := createURL(endpointClient())
+	expected := endpoint + "v2.0/subnets"
 	th.AssertEquals(t, expected, actual)
 }
 
 func TestUpdateURL(t *testing.T) {
-	actual := UpdateURL(EndpointClient(), "foo")
-	expected := Endpoint + "v2.0/subnets/foo"
+	actual := updateURL(endpointClient(), "foo")
+	expected := endpoint + "v2.0/subnets/foo"
 	th.AssertEquals(t, expected, actual)
 }
 
 func TestDeleteURL(t *testing.T) {
-	actual := DeleteURL(EndpointClient(), "foo")
-	expected := Endpoint + "v2.0/subnets/foo"
+	actual := deleteURL(endpointClient(), "foo")
+	expected := endpoint + "v2.0/subnets/foo"
 	th.AssertEquals(t, expected, actual)
 }