This material is derived from I.C. Hierarchically Structure Objectives in Wizard. Go there if you need more help.



It sounds redundant, but an objectives hierarchy is simply a hierarchical arrangement of objectives. Objectives in the top or upper levels of the hierarchy reflect broad or inclusive values. Progress towards these objectives is indicated by progress towards narrower, more specific objectives arrayed under the upper level. Thus, any alternative can be viewed in context of a broader objective to which it contributes, and also to more specific objectives that contribute to it. For example, an individual might array a series of objectives under the general or fundamental objective to maintain physical fitness:

  • maintain physical fitness
    • exercise regularly
      • jog 3 times a week
      • do strength training twice weekly
    • control diet
      • limit calories
      • eat balanced meals

As this simple example illustrates, the more general objective is gradually decomposed into more specific and measurable objectives. The transition is from "Why?" at higher levels, to "How?" at lower levels. These lower-level objectives eventually include specific actions, why is why they are often referred to as "means objectives." At some point they can be specified in measurable terms.

Objective hierarchies can be constructed from either the top down, or from the bottom up. The "top-down" and "bottom-up" approaches to building an objectives hierarchy follow simple rules (Figure 1), The two approaches provide flexibility, recognizing that risk assessments and planning exercises often begin with a narrow view of a larger problem.

Top-Down Approach

A fundamental objective can be decomposed into more detailed fundamental objectives, or into one or more means objectives that help accomplish the fundamental objective. In the case of fundamental objectives, questions such as What is important about this objective? or What are the key components of this objective? are asked. Almost any fundamental objectives can be partitioned into spatial, temporal, or other conceptual categories. The purpose is to create "manageable" objectives by identifying manageable categories, e.g., relating to geographical boundaries, stages in a life cycle, or economic vs. ecological aspects of the decision problem. By reducing vague or general fundamental objectives into more specific objectives, users are better able to identify or customize relevant management activities.

Figure 1. How to construct an objectives hierarchy
(Modified from Clemen, 1996:47)

At some point in the "top-down" process, it will become obvious that a fundamental objective is sufficiently specific for at least one of the following: (1) monitoring indicators or measures can be selected or designed; (2) means objectives that contribute to the achievement of the fundamental objective can be identified. In the latter case, the "top-down" approach continues with further development of means-objectives. By answering the questions How does this happen? or How could I achieve this?, a chain of cause-and-effect between fundamental objectives and management activities is constructed via effects in the managed ecosystem. This process not only helps identify a wider range of candidate management activities, but also begins to flesh out a team's understanding of how the ecosystem may (or may not) propagate management actions into the realm of social values.


Example of the Top-down Approach: Narrowing the Focus

Scenario: A planning team is formulating an approach to maintain and restore forest health in late-successional reserves (LSRs) in a national forest under the Northwest Forest Plan.

The top-down approach to building an objectives hierarchy is a sequential process of narrowing a team's focus from broad to specific objectives using "what" and "how" questions. In this example, a known fundamental objective is "decomposed", or broken down into more detailed fundamental objectives and eventually into several means objectives that help accomplish fundamental objectives (Figure 1). A planning team has identified a fundamental objective, or desired future condition, Healthy LSRs. With this (and each fundamental objective identified), the team proceeds to ask, What is important about this objective? or What are the key components of this objective? This team concludes that Healthy LSRs can be fully addressed within their decision context by decomposing it into two fundamental sub-objectives (or desired future conditions): Restore Natural Fire Regimes and Protect from Uncharacteristic Wildfires. Note that the two fundamental objectives do not fully define Healthy LSRs in a scientific or managerial sense, but only circumscribe the project's contribution to Healthy LSRs. Obviously, there are many other aspects of LSRs not addressed here that might define what is meant by "healthy" .

Figure 1. Objectives hierarchy developed in the top-down example.
Objectives Hierarchy Top Down Approach

How long does this top-down process of creating new fundamental objectives continue? It's difficult to prescribe strict rules, but once a fundamental objective starts to sound "manageable", i.e., specific management prescriptions, indicators, or measures become apparent, then it may be appropriate for the team to begin identifying means objectives. To identify means objectives, for each lowest-level fundamental objective the team asks, How do we accomplish this? In this example, the team perceives that the main threat risk to future LSR health is wildfire. They select Reduce Wildfire Hazard as an appropriate means to Protect from Uncharacteristic Wildfires and Restore Natural Fire Regime.

Clearly, however, the means objective Reduce Wildfire Hazard is too vague to constitute a management prescription. By continuing to ask, How do we accomplish this?, the team reveals subordinate means objectives, in this case Reduce Fuel Loads. By further continuing this line of questioning, the two objectives, Prescribed Fire and Mechanical Fuels Reduction are identified as means, or strategies by which higher-level means and fundamental objectives can be accomplished. By continuing the“decomposition” process, specific management activities can be defined (e.g., geographically specific prescriptions). The resulting objectives hierarchy and means network then clearly map how each activity contributes to the fundamental objectives that are driving the current project.


Bottom-Up Approach

While the top-down approach seems more logical (particularly as planning processes often begin with values and objectives), initial conversations among participants may center on a perceived need for specific management activities, their effects, or potentially hazardous events. A bottom-up approach attempts to derive appropriate fundamental objectives for a given set of issues, concerns, or proposed management activities. It begins by asking the question Why do we want to do this ? or What does this event cause? For example, the means objective Reduce Live Fuels may influence the achievement of fundamental objectives relating to biodiversity conservation and community protection from wildfire, but it does so via a web of interacting variables in the ecosystem. Thus, Reduce Live Fuels is the means to an end (fundamental objectives) as well as a means to reduce leaf area index, increase insolation, increase drying of fuels, increase productivity of understory plants, increase ground wind, etc. By building a preliminary web of interactions in the form of a means objective network, users may be led to consider different fundamental objectives as well as unseen interactions and tradeoffs among objectives.

Example of the Bottom-up Approach: Initial Focus on Activities

Scenario: A planning team and various stakeholder groups are formulating a collaborative restoration approach addressing the threats and risks of hazardous fuels and wildfire at the wildland-urban interface (WUI) along a major river corridor in a national forest.

The bottom-up approach to building an objectives hierarchy is a sequential process of broadening a team's narrow focus on specific threats, issues, or management prescription to derive more fundamental objectives. It uses mainly "why" questions. It is a process of discovery that helps clarify and identify fundamental objectives, and may even uncover "hidden" objectives (Keeney, 1992) that can expand or re-define the decision context.

In this example, the bottom-up approach helps a planning team and other stakeholders whose main reason for undertaking a risk assessment action is the threat of wildfire. In such a case, the conversations within the team and stakeholder groups may already be focusing on a specific management strategy (means objective) for mitigating wildfire risk, Mechanical Fuels Reduction (Figure 2). While a narrow initial focus is to be expected, defining the scope of the project (i.e., the decision context) and conducting a risk assessment may require a more extensive exploration of "decision space". The bottom up approach facilitates this.

Figure 2. Objectives hierarchy developed in the bottom-up example.

Objectives Hierarchy Bottom Up Approach

In the bottom-up approach, Mechanical Fuels Reduction is the point of departure for the team and its partners. The goal is to identify or clarify broader objectives and additional management options. First, the team asks, Why is this objective important? In this example, their response is that it will Reduce Fuel Loads (Figure 2). Having identified this higher-level means objectives, the team now considers the question, What can help achieve this objective? Their answer is Prescribed Fire. As in the top-down example, specific management prescriptions might be defined by continuing to “decompose” these two strategies.

At this point the team re-directs its attention to the means objective, Reduce Fuel Loads, again asking Why is this objective important? They make the obvious conclusion that it would be a means to Reduce Wildfire Hazard, and proceed to again ask Why is this objective important? At this point in the exercise, the team realizes there are numerous answers to the question, some outside the scope of their project. But because the team's initial focus was restoration, the team understands that the objective Reduce Wildfire Hazard is a means for moving the ecosystem towards two important desired future conditions (i.e., fundamental objectives), represented by Restore Natural Fire Regime and Protect from Uncharacteristic Wildfires.

As before in the top-down approach, the team shifts its perception from means objectives to fundamental objectives. The members feel that Natural Fire Regime and Protected from Uncharacteristic Wildfires are really statements about desired future conditions, fundamental to the entire forest plan and not likely to be achieved by any individual project.

To continue the same line of questioning for Natural Fire Regime and Protected from Uncharacteristic Wildfires, the team asks Why is this objective important? Given the nature of the project, their answer may be simply, "it just is". Such feelings about a fundamental objective may reflect commonly held values within the team. For example, values-based objectives may derive from existing plans, laws, regulations, or policies. It's important to identify and state these higher-level connections, for in doing so, other more hidden objectives may emerge. The team decides to state the "obvious". They link Natural Fire Regime and Protected from Uncharacteristic with their conception of the the project's fundamental objective: Restore Forest Health in the Wildland-Urban Interface (WUI).

In this example, the exercise of stating (and documenting) the obvious prompts a conversation about forest health among a diverse set of stakeholder groups. For some, forest health, like ecosystem health, implies a strong connection between ecological and economic integrity. The river corridor along which the project is situated is well-known to commercial mushroom harvesters who are concerned that management prescriptions also address their needs. The team decides to include the fundamental objective Improve Mushroom Harvest under Restore Forest Health in the WUI.

Because the ecology and management of fungi that fruit in fall versus spring differ so markedly, they are represented by distinct fundamental objectives (Figure 2). It's noted that Prescribed Fire will likely improve spring harvests of morrels, while Improved Access to foot traffic will help harvesters during both seasons. Most importantly, the consideration of "hidden" fundamental objectives has facilitated a re-thinking about design, placement, and timing of management prescriptions for fire and fuels to account for various mushroom species and their harvests.

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