diff --git a/groups.go b/groups.go
index 4b7713912..dda5c306e 100644
--- a/groups.go
+++ b/groups.go
@@ -18,10 +18,13 @@ package gitlab
 
 import (
 	"bytes"
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
 	"time"
+
+	retryablehttp "github.com/hashicorp/go-retryablehttp"
 )
 
 // GroupsService handles communication with the group related methods of
@@ -90,6 +93,15 @@ type GroupAvatar struct {
 	Image    io.Reader
 }
 
+// MarshalJSON implements the json.Marshaler interface.
+func (a *GroupAvatar) MarshalJSON() ([]byte, error) {
+	if a.Filename == "" && a.Image == nil {
+		return []byte(`""`), nil
+	}
+	type alias GroupAvatar
+	return json.Marshal((*alias)(a))
+}
+
 // LDAPGroupLink represents a GitLab LDAP group link.
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/groups.html#ldap-group-links
@@ -312,6 +324,7 @@ func (s *GroupsService) DownloadAvatar(gid interface{}, options ...RequestOption
 type CreateGroupOptions struct {
 	Name                           *string                     `url:"name,omitempty" json:"name,omitempty"`
 	Path                           *string                     `url:"path,omitempty" json:"path,omitempty"`
+	Avatar                         *GroupAvatar                `url:"-" json:"-"`
 	Description                    *string                     `url:"description,omitempty" json:"description,omitempty"`
 	MembershipLock                 *bool                       `url:"membership_lock,omitempty" json:"membership_lock,omitempty"`
 	Visibility                     *VisibilityValue            `url:"visibility,omitempty" json:"visibility,omitempty"`
@@ -336,7 +349,22 @@ type CreateGroupOptions struct {
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/groups.html#new-group
 func (s *GroupsService) CreateGroup(opt *CreateGroupOptions, options ...RequestOptionFunc) (*Group, *Response, error) {
-	req, err := s.client.NewRequest(http.MethodPost, "groups", opt, options)
+	var err error
+	var req *retryablehttp.Request
+
+	if opt.Avatar != nil {
+		req, err = s.client.NewRequest(http.MethodPost, "groups", opt, options)
+	} else {
+		req, err = s.client.UploadRequest(
+			http.MethodPost,
+			"groups",
+			opt.Avatar.Image,
+			opt.Avatar.Filename,
+			UploadAvatar,
+			opt,
+			options,
+		)
+	}
 	if err != nil {
 		return nil, nil, err
 	}
@@ -420,6 +448,7 @@ func (s *GroupsService) TransferSubGroup(gid interface{}, opt *TransferSubGroupO
 type UpdateGroupOptions struct {
 	Name                                 *string                     `url:"name,omitempty" json:"name,omitempty"`
 	Path                                 *string                     `url:"path,omitempty" json:"path,omitempty"`
+	Avatar                               *GroupAvatar                `url:"-" json:"avatar,omitempty"`
 	Description                          *string                     `url:"description,omitempty" json:"description,omitempty"`
 	MembershipLock                       *bool                       `url:"membership_lock,omitempty" json:"membership_lock,omitempty"`
 	Visibility                           *VisibilityValue            `url:"visibility,omitempty" json:"visibility,omitempty"`
@@ -453,7 +482,21 @@ func (s *GroupsService) UpdateGroup(gid interface{}, opt *UpdateGroupOptions, op
 	}
 	u := fmt.Sprintf("groups/%s", PathEscape(group))
 
-	req, err := s.client.NewRequest(http.MethodPut, u, opt, options)
+	var req *retryablehttp.Request
+
+	if opt.Avatar == nil || (opt.Avatar.Filename == "" && opt.Avatar.Image == nil) {
+		req, err = s.client.NewRequest(http.MethodPut, u, opt, options)
+	} else {
+		req, err = s.client.UploadRequest(
+			http.MethodPut,
+			u,
+			opt.Avatar.Image,
+			opt.Avatar.Filename,
+			UploadAvatar,
+			opt,
+			options,
+		)
+	}
 	if err != nil {
 		return nil, nil, err
 	}
diff --git a/projects.go b/projects.go
index 1aadf902b..1bef75f98 100644
--- a/projects.go
+++ b/projects.go
@@ -17,6 +17,7 @@
 package gitlab
 
 import (
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -704,6 +705,15 @@ type ProjectAvatar struct {
 	Image    io.Reader
 }
 
+// MarshalJSON implements the json.Marshaler interface.
+func (a *ProjectAvatar) MarshalJSON() ([]byte, error) {
+	if a.Filename == "" && a.Image == nil {
+		return []byte(`""`), nil
+	}
+	type alias ProjectAvatar
+	return json.Marshal((*alias)(a))
+}
+
 // CreateProject creates a new project owned by the authenticated user.
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/projects.html#create-project
@@ -805,7 +815,7 @@ type EditProjectOptions struct {
 	AutoDevopsDeployStrategy                  *string                              `url:"auto_devops_deploy_strategy,omitempty" json:"auto_devops_deploy_strategy,omitempty"`
 	AutoDevopsEnabled                         *bool                                `url:"auto_devops_enabled,omitempty" json:"auto_devops_enabled,omitempty"`
 	AutocloseReferencedIssues                 *bool                                `url:"autoclose_referenced_issues,omitempty" json:"autoclose_referenced_issues,omitempty"`
-	Avatar                                    *ProjectAvatar                       `url:"-" json:"-"`
+	Avatar                                    *ProjectAvatar                       `url:"-" json:"avatar,omitempty"`
 	BuildCoverageRegex                        *string                              `url:"build_coverage_regex,omitempty" json:"build_coverage_regex,omitempty"`
 	BuildGitStrategy                          *string                              `url:"build_git_strategy,omitempty" json:"build_git_strategy,omitempty"`
 	BuildTimeout                              *int                                 `url:"build_timeout,omitempty" json:"build_timeout,omitempty"`
@@ -893,7 +903,7 @@ func (s *ProjectsService) EditProject(pid interface{}, opt *EditProjectOptions,
 
 	var req *retryablehttp.Request
 
-	if opt.Avatar == nil {
+	if opt.Avatar == nil || (opt.Avatar.Filename == "" && opt.Avatar.Image == nil) {
 		req, err = s.client.NewRequest(http.MethodPut, u, opt, options)
 	} else {
 		req, err = s.client.UploadRequest(
diff --git a/users.go b/users.go
index bbe535a10..6fc6b2303 100644
--- a/users.go
+++ b/users.go
@@ -17,11 +17,15 @@
 package gitlab
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
+	"io"
 	"net"
 	"net/http"
 	"time"
+
+	retryablehttp "github.com/hashicorp/go-retryablehttp"
 )
 
 // List a couple of standard errors.
@@ -109,6 +113,23 @@ type UserIdentity struct {
 	ExternUID string `json:"extern_uid"`
 }
 
+// UserAvatar represents a GitLab user avatar.
+//
+// GitLab API docs: https://docs.gitlab.com/ce/api/users.html
+type UserAvatar struct {
+	Filename string
+	Image    io.Reader
+}
+
+// MarshalJSON implements the json.Marshaler interface.
+func (a *UserAvatar) MarshalJSON() ([]byte, error) {
+	if a.Filename == "" && a.Image == nil {
+		return []byte(`""`), nil
+	}
+	type alias UserAvatar
+	return json.Marshal((*alias)(a))
+}
+
 // ListUsersOptions represents the available ListUsers() options.
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/users.html#list-users
@@ -184,37 +205,53 @@ func (s *UsersService) GetUser(user int, opt GetUsersOptions, options ...Request
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/users.html#user-creation
 type CreateUserOptions struct {
-	Email               *string `url:"email,omitempty" json:"email,omitempty"`
-	Password            *string `url:"password,omitempty" json:"password,omitempty"`
-	ResetPassword       *bool   `url:"reset_password,omitempty" json:"reset_password,omitempty"`
-	ForceRandomPassword *bool   `url:"force_random_password,omitempty" json:"force_random_password,omitempty"`
-	Username            *string `url:"username,omitempty" json:"username,omitempty"`
-	Name                *string `url:"name,omitempty" json:"name,omitempty"`
-	Skype               *string `url:"skype,omitempty" json:"skype,omitempty"`
-	Linkedin            *string `url:"linkedin,omitempty" json:"linkedin,omitempty"`
-	Twitter             *string `url:"twitter,omitempty" json:"twitter,omitempty"`
-	WebsiteURL          *string `url:"website_url,omitempty" json:"website_url,omitempty"`
-	Organization        *string `url:"organization,omitempty" json:"organization,omitempty"`
-	JobTitle            *string `url:"job_title,omitempty" json:"job_title,omitempty"`
-	ProjectsLimit       *int    `url:"projects_limit,omitempty" json:"projects_limit,omitempty"`
-	ExternUID           *string `url:"extern_uid,omitempty" json:"extern_uid,omitempty"`
-	Provider            *string `url:"provider,omitempty" json:"provider,omitempty"`
-	Bio                 *string `url:"bio,omitempty" json:"bio,omitempty"`
-	Location            *string `url:"location,omitempty" json:"location,omitempty"`
-	Admin               *bool   `url:"admin,omitempty" json:"admin,omitempty"`
-	CanCreateGroup      *bool   `url:"can_create_group,omitempty" json:"can_create_group,omitempty"`
-	SkipConfirmation    *bool   `url:"skip_confirmation,omitempty" json:"skip_confirmation,omitempty"`
-	External            *bool   `url:"external,omitempty" json:"external,omitempty"`
-	PrivateProfile      *bool   `url:"private_profile,omitempty" json:"private_profile,omitempty"`
-	Note                *string `url:"note,omitempty" json:"note,omitempty"`
-	ThemeID             *int    `url:"theme_id,omitempty" json:"theme_id,omitempty"`
+	Avatar              *UserAvatar `url:"-" json:"-"`
+	Email               *string     `url:"email,omitempty" json:"email,omitempty"`
+	Password            *string     `url:"password,omitempty" json:"password,omitempty"`
+	ResetPassword       *bool       `url:"reset_password,omitempty" json:"reset_password,omitempty"`
+	ForceRandomPassword *bool       `url:"force_random_password,omitempty" json:"force_random_password,omitempty"`
+	Username            *string     `url:"username,omitempty" json:"username,omitempty"`
+	Name                *string     `url:"name,omitempty" json:"name,omitempty"`
+	Skype               *string     `url:"skype,omitempty" json:"skype,omitempty"`
+	Linkedin            *string     `url:"linkedin,omitempty" json:"linkedin,omitempty"`
+	Twitter             *string     `url:"twitter,omitempty" json:"twitter,omitempty"`
+	WebsiteURL          *string     `url:"website_url,omitempty" json:"website_url,omitempty"`
+	Organization        *string     `url:"organization,omitempty" json:"organization,omitempty"`
+	JobTitle            *string     `url:"job_title,omitempty" json:"job_title,omitempty"`
+	ProjectsLimit       *int        `url:"projects_limit,omitempty" json:"projects_limit,omitempty"`
+	ExternUID           *string     `url:"extern_uid,omitempty" json:"extern_uid,omitempty"`
+	Provider            *string     `url:"provider,omitempty" json:"provider,omitempty"`
+	Bio                 *string     `url:"bio,omitempty" json:"bio,omitempty"`
+	Location            *string     `url:"location,omitempty" json:"location,omitempty"`
+	Admin               *bool       `url:"admin,omitempty" json:"admin,omitempty"`
+	CanCreateGroup      *bool       `url:"can_create_group,omitempty" json:"can_create_group,omitempty"`
+	SkipConfirmation    *bool       `url:"skip_confirmation,omitempty" json:"skip_confirmation,omitempty"`
+	External            *bool       `url:"external,omitempty" json:"external,omitempty"`
+	PrivateProfile      *bool       `url:"private_profile,omitempty" json:"private_profile,omitempty"`
+	Note                *string     `url:"note,omitempty" json:"note,omitempty"`
+	ThemeID             *int        `url:"theme_id,omitempty" json:"theme_id,omitempty"`
 }
 
 // CreateUser creates a new user. Note only administrators can create new users.
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/users.html#user-creation
 func (s *UsersService) CreateUser(opt *CreateUserOptions, options ...RequestOptionFunc) (*User, *Response, error) {
-	req, err := s.client.NewRequest(http.MethodPost, "users", opt, options)
+	var err error
+	var req *retryablehttp.Request
+
+	if opt.Avatar == nil {
+		req, err = s.client.NewRequest(http.MethodPost, "users", opt, options)
+	} else {
+		req, err = s.client.UploadRequest(
+			http.MethodPost,
+			"users",
+			opt.Avatar.Image,
+			opt.Avatar.Filename,
+			UploadAvatar,
+			opt,
+			options,
+		)
+	}
 	if err != nil {
 		return nil, nil, err
 	}
@@ -232,29 +269,30 @@ func (s *UsersService) CreateUser(opt *CreateUserOptions, options ...RequestOpti
 //
 // GitLab API docs: https://docs.gitlab.com/ce/api/users.html#user-modification
 type ModifyUserOptions struct {
-	Email              *string `url:"email,omitempty" json:"email,omitempty"`
-	Password           *string `url:"password,omitempty" json:"password,omitempty"`
-	Username           *string `url:"username,omitempty" json:"username,omitempty"`
-	Name               *string `url:"name,omitempty" json:"name,omitempty"`
-	Skype              *string `url:"skype,omitempty" json:"skype,omitempty"`
-	Linkedin           *string `url:"linkedin,omitempty" json:"linkedin,omitempty"`
-	Twitter            *string `url:"twitter,omitempty" json:"twitter,omitempty"`
-	WebsiteURL         *string `url:"website_url,omitempty" json:"website_url,omitempty"`
-	Organization       *string `url:"organization,omitempty" json:"organization,omitempty"`
-	JobTitle           *string `url:"job_title,omitempty" json:"job_title,omitempty"`
-	ProjectsLimit      *int    `url:"projects_limit,omitempty" json:"projects_limit,omitempty"`
-	ExternUID          *string `url:"extern_uid,omitempty" json:"extern_uid,omitempty"`
-	Provider           *string `url:"provider,omitempty" json:"provider,omitempty"`
-	Bio                *string `url:"bio,omitempty" json:"bio,omitempty"`
-	Location           *string `url:"location,omitempty" json:"location,omitempty"`
-	Admin              *bool   `url:"admin,omitempty" json:"admin,omitempty"`
-	CanCreateGroup     *bool   `url:"can_create_group,omitempty" json:"can_create_group,omitempty"`
-	SkipReconfirmation *bool   `url:"skip_reconfirmation,omitempty" json:"skip_reconfirmation,omitempty"`
-	External           *bool   `url:"external,omitempty" json:"external,omitempty"`
-	PrivateProfile     *bool   `url:"private_profile,omitempty" json:"private_profile,omitempty"`
-	Note               *string `url:"note,omitempty" json:"note,omitempty"`
-	ThemeID            *int    `url:"theme_id,omitempty" json:"theme_id,omitempty"`
-	PublicEmail        *string `url:"public_email,omitempty" json:"public_email,omitempty"`
+	Avatar             *UserAvatar `url:"-" json:"avatar,omitempty"`
+	Email              *string     `url:"email,omitempty" json:"email,omitempty"`
+	Password           *string     `url:"password,omitempty" json:"password,omitempty"`
+	Username           *string     `url:"username,omitempty" json:"username,omitempty"`
+	Name               *string     `url:"name,omitempty" json:"name,omitempty"`
+	Skype              *string     `url:"skype,omitempty" json:"skype,omitempty"`
+	Linkedin           *string     `url:"linkedin,omitempty" json:"linkedin,omitempty"`
+	Twitter            *string     `url:"twitter,omitempty" json:"twitter,omitempty"`
+	WebsiteURL         *string     `url:"website_url,omitempty" json:"website_url,omitempty"`
+	Organization       *string     `url:"organization,omitempty" json:"organization,omitempty"`
+	JobTitle           *string     `url:"job_title,omitempty" json:"job_title,omitempty"`
+	ProjectsLimit      *int        `url:"projects_limit,omitempty" json:"projects_limit,omitempty"`
+	ExternUID          *string     `url:"extern_uid,omitempty" json:"extern_uid,omitempty"`
+	Provider           *string     `url:"provider,omitempty" json:"provider,omitempty"`
+	Bio                *string     `url:"bio,omitempty" json:"bio,omitempty"`
+	Location           *string     `url:"location,omitempty" json:"location,omitempty"`
+	Admin              *bool       `url:"admin,omitempty" json:"admin,omitempty"`
+	CanCreateGroup     *bool       `url:"can_create_group,omitempty" json:"can_create_group,omitempty"`
+	SkipReconfirmation *bool       `url:"skip_reconfirmation,omitempty" json:"skip_reconfirmation,omitempty"`
+	External           *bool       `url:"external,omitempty" json:"external,omitempty"`
+	PrivateProfile     *bool       `url:"private_profile,omitempty" json:"private_profile,omitempty"`
+	Note               *string     `url:"note,omitempty" json:"note,omitempty"`
+	ThemeID            *int        `url:"theme_id,omitempty" json:"theme_id,omitempty"`
+	PublicEmail        *string     `url:"public_email,omitempty" json:"public_email,omitempty"`
 }
 
 // ModifyUser modifies an existing user. Only administrators can change attributes
@@ -264,7 +302,22 @@ type ModifyUserOptions struct {
 func (s *UsersService) ModifyUser(user int, opt *ModifyUserOptions, options ...RequestOptionFunc) (*User, *Response, error) {
 	u := fmt.Sprintf("users/%d", user)
 
-	req, err := s.client.NewRequest(http.MethodPut, u, opt, options)
+	var err error
+	var req *retryablehttp.Request
+
+	if opt.Avatar == nil || (opt.Avatar.Filename == "" && opt.Avatar.Image == nil) {
+		req, err = s.client.NewRequest(http.MethodPut, u, opt, options)
+	} else {
+		req, err = s.client.UploadRequest(
+			http.MethodPut,
+			u,
+			opt.Avatar.Image,
+			opt.Avatar.Filename,
+			UploadAvatar,
+			opt,
+			options,
+		)
+	}
 	if err != nil {
 		return nil, nil, err
 	}