Difficult Points

Business Associations

Piercing the Corporate Veil: Determining when to hold shareholders personally liable for corporate debts can be tricky. This involves analyzing factors like undercapitalization, commingling of funds, and fraud to decide if the corporate form should be disregarded.
Fiduciary Duties: Applying the duties of care and loyalty to directors and officers requires careful analysis of their actions in relation to the corporation and its shareholders.
Agency and Partnership vs. Corporations Rules: It's easy to confuse rules of agency and management with those specific to corporations. For example, understanding how partner liability differs from shareholder liability is key.

Civil Procedure

Jurisdiction: This is a perennial trouble spot, encompassing personal jurisdiction, subject matter jurisdiction (diversity and supplemental), and venue.
Erie Doctrine: Figuring out whether federal or state law applies in a diversity case can be complex, requiring a nuanced understanding of the interplay between the two.
Preclusion: Applying claim and issue preclusion involves analyzing the impact of prior judgments on subsequent lawsuits, which can be challenging.

Conflicts of Law

Choice of Law: Determining which jurisdiction's law applies to a case with connections to multiple states can be complex, especially when considering different approaches like the "most significant relationship" test.
Recognition of Judgments: Understanding the rules for recognizing and enforcing judgments from other states (or countries) can be tricky, particularly when dealing with issues like domicile and full faith and credit.

Contracts

Formation: Mastering offer, acceptance, and consideration, especially under the UCC for goods contracts, can be difficult.
Statute of Frauds: Knowing when a contract must be in writing to be enforceable is crucial, and the various exceptions to this rule can be confusing.
Remedies: Calculating damages, and understanding equitable remedies like specific performance, can be challenging.

Constitutional Law

Individual Rights: This broad area covers First Amendment freedoms, due process, equal protection, and criminal procedure rights, requiring knowledge of landmark cases and nuanced application.
Levels of Scrutiny: Applying strict scrutiny, intermediate scrutiny, and rational basis review to different types of government action can be tricky.
State Action Doctrine: Understanding when private conduct is subject to constitutional limitations can be challenging.

Criminal Law & Procedure

Homicide: Distinguishing between murder (with its degrees and variations like felony murder), manslaughter, and lesser offenses requires careful analysis of intent and circumstances.
Inchoate Crimes: Understanding attempt, conspiracy, and solicitation, including the required mental states and elements for each, can be difficult.
Fourth Amendment: Applying the rules on search and seizure, including warrant requirements, exceptions, and the exclusionary rule, can be complex.

Evidence

Hearsay: Mastering the hearsay rule and its many exceptions is a major challenge, requiring careful analysis of out-of-court statements and their purpose.
Character Evidence: Knowing when character evidence is admissible and for what purpose (e.g., propensity, impeachment) can be tricky.
Impeachment: Understanding the various methods of attacking a witness's credibility, and the rules governing each, can be complex.

Family Law

Jurisdiction: Interstate custody and support disputes raise complex jurisdictional issues under the UCCJEA and UIFSA.
Division of Property: Classifying property as marital or separate, and applying the rules for equitable distribution, can be challenging.
Child Custody and Support: Applying the "best interests of the child" standard and understanding modification rules can be difficult.

Wills, Trusts & Estates

Future Interests: Grasping reversions, remainders, executory interests, and the Rule Against Perpetuities is notoriously difficult.
Trust Formation and Validity: Understanding the requirements for creating valid trusts, including intent, trust property, and beneficiaries, can be challenging.
Will Contests: Knowing the grounds for contesting a will, such as undue influence or lack of capacity, and the evidentiary rules involved, can be complex.

Professional Responsibility

Conflicts of Interest: Identifying and analyzing different types of conflicts, and applying the rules for imputation and disqualification, can be challenging.
Confidentiality: Understanding the duty of confidentiality and its exceptions, such as mandatory reporting obligations, can be tricky.
Attorney-Client Privilege: Distinguishing between the duty of confidentiality and the attorney-client privilege, and knowing when the privilege applies and can be waived, can be difficult.